Millennium LIQUID CHILLERS AIR-COOLED – …

108
60 HZ MODELS YCAJ110-130 200, 230, 460-3-60 * With EPROM 031-01652-001 (Standard, Brine & Metric Models, Combined) INSTALL., OPER., MAINT. Supersedes: See Back Form 150.60-NM5 (398) Millennium TM LIQUID CHILLERS AIR-COOLED – RECIPROCATING HERMETIC

Transcript of Millennium LIQUID CHILLERS AIR-COOLED – …

Page 1: Millennium LIQUID CHILLERS AIR-COOLED – …

60 HZ MODELSYCAJ110-130

200, 230, 460-3-60

* With EPROM 031-01652-001 (Standard, Brine & Metric Models, Combined)

INSTALL., OPER., MAINT. Supersedes: See Back Form 150.60-NM5 (398)

Millennium TM LIQUID CHILLERSAIR-COOLED – RECIPROCATING HERMETIC

28694A

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TABLE OF CONTENTS

General Information .......................................................................................... 2Unit Nomenclature ........................................................................................... 3Compressor Nomenclature ............................................................................... 3Unit Components ............................................................................................. 4Compressor Components ................................................................................. 5Operational Limitations..................................................................................... 6Physical Data .................................................................................................. 8Dimensions ...................................................................................................... 10Electrical Data ................................................................................................. 12Installation ........................................................................................................ 16Weight Distribution and Isolator Locations ........................................................ 18Wiring Diagrams .............................................................................................. 20Unit Controls and Operation ............................................................................. 29Display Keys.................................................................................................... 32Status Key ....................................................................................................... 37Entry Keys ....................................................................................................... 40Program Key .................................................................................................... 41Clock Keys ...................................................................................................... 45Selection of Return or Leaving Chilled Liquid .................................................... 48Setpoints Keys ................................................................................................ 49System Safeties .............................................................................................. 57Print Keys ........................................................................................................ 63Unit On / Off Switch ......................................................................................... 69Compressor Capacity Control ........................................................................... 77System Startup Checklist ................................................................................ 78Preventative Maintenance ................................................................................. 83Options ............................................................................................................ 85Troubleshooting Chart ...................................................................................... 102Temperature Conversion Tables ........................................................................ 106

GENERAL INFORMATION

GENERAL DESCRIPTION

These packaged liquid chillers are completely self-contained outdoor units shipped ready for final job instal-lation requiring only liquid connections, power and controlwiring. They are designed primarily for central station airconditioning applications with normal installations beingon roof-tops or on ground level beside the building.

CODE STATUS

The units are designed in accordance with UL (200, 230,460-3-60), N.E.C., ASHRAE/ANSI STANDARD 15, andASME Codes.

WARNING HIGH VOLTAGE

is used in the operation of this equipment.DEATH OR SERIOUS INJURY

may result if personnel fail to observe safety precautions.Work on electronic equipment should not be undertaken unless the individual(s) have been trained in the propermaintenance of equipment and is (are) familiar with its potential hazards.

Shut off power supply to equipment before beginning work and follow lockout procedures. When working insideequipment with power off, take care to discharge every capacitor likely to hold dangerous potential.

Be careful not to contact high voltage connections when installing or operating this equipment.

LOW VOLTAGE

DO NOT be misled by the term low voltage.Voltages as low as 50 volts may cause death.

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UNIT NOMENCLATURE

Compressor Series

Compressor Style (G or K)

No. of Active Cylinders (4)

Stroke (3, 4)

Steps of Unloading

Motor Size (M, N, P, Q, S, T, V)

Voltage Code:17 = 200-3-6028 = 230-6040 = 380-3-6046 = 460-3-6050 = 380/415-3-5058 = 575-3-6064 = 346-3-50

Motor Manufacturer (S = A.O. Smith, L = Lacy Somer)

J G 4 3 3 T -17 S

YC A J 110 — 46 P A

Chiller: Design Level YC = YORK Chiller

Type StartP = Part Wind

Air Cooled

Compressor TypeJ – Reciprocating Voltage Code:

17 = 200-3-60Unit Model 28 = 230-3-60

40 = 380-3-6046 = 460-3-6058 = 575-3-60

COMPRESSOR NOMENCLATURE

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FIG. 1 UNIT COMPONENTS

28694A

25996A

LD02694

CONTROLPANEL

POWERPANEL

COOLER

DATA PLATE

CONTROLWIRINGCONDUIT

CONDENSERFANS

HOT GASBYPASS

THERMOSTATICALLYCONTROLLED

HEATER

THERMALEXPANSION

VALVES

COOLER

CHILLED WATEROUTLET

HOT GASBYPASS

SYSTEM #1

POWER WIRING

CHILLED WATERINLET

28695A

CONDENSERCOILS

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FIG. 2 COMPRESSOR COMPONENTS

COMPRESSOR TERMINAL BOX

8-CYLINDERMODEL J COMPRESSOR

27299A

27597A

MOTORTERMINALS

SUPPRESSORS

MOTORPROTECTOR(MP)

DISCHARGESTOP VALVE

OIL PRESSUREACCESS CONN.

SIGHTGLASSES

OIL CHARGINGVALVE

CAPACITYCONTROLSOLENOID

SUCTIONSTOPVALVE

RAINTIGHTTERMINALBOX

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LD02695

OPERATIONAL LIMITATIONS (English)

VOLTAGE LIMITATIONS

The following voltage limitations are absolute and opera-tion beyond these limitations may cause serious dam-age to the compressor.

VOLTAGES

TEMPERATURES AND FLOWS

NOTES:

1. Standard units cannot be operated below 40°F leaving chilledliquid temperature.

2. Operation below 25°F requires the Optional Low Ambient kit(Minimum recommended operating temperature is 0°F).

3. Operation above 115°F requires Optional High Ambient kit(Maximum recommended operating temperature is 130°F).

4. The evaporator is protected against freeze-up to -20°F with anelectrical heater cable as standard.

CAUTION: Excessive flow will cause damage to thecooler. Do not exceed max. cooler GPM.Special care should be taken when mul-tiple chillers are fed by a single pump.

UNIT POWER MIN. MAX.

200-3-60 180 220

230-3-60 207 253

380-3-60 355 415

460-3-60 414 506

380/415-3-50 342 440

346-3-50 311 381

575-3-60 517 633

COOLER KEY

CODE MODEL

H YCAJ110, 120, 130

FIG. 3A COOLER WATER PRESSURE DROP (English)

MODELLVG.WATER COOLER AIR ON

YCATEMP. °F GPM CONDENSER °F

MIN.1 MAX. MIN. MAX. MIN.2 MAX.3

J110 40 50 150 640 0 130

J120 40 50 150 640 0 130

J130 40 50 150 640 0 130

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LD02696

OPERATIONAL LIMITATIONS (SI)

VOLTAGE LIMITATIONS

The following voltage limitations are absolute and opera-tion beyond these limitations may cause serious dam-age to the compressor.

VOLTAGES

TEMPERATURES AND FLOWS

NOTES:

1. Standard units cannot be operated below 4.4°C leaving chilledliquid temperature.

2. Operation below -3.9°C requires the Optional Low Ambient kit(Minimum recommended operating temperature is -17.8°C).

3. Operation above 46.1°C requires Optional High Ambient kit(Maximum recommended operating temperature is 54.4°C).

4. The evaporator is protected against freeze-up to -28.9°C withan electrical heater cable as standard.

CAUTION: Excessive flow will cause damage to thecooler. Do not exceed max. cooler flow.Special care should be taken when mul-tiple chillers are fed by a single pump.

FIG. 3B COOLER WATER PRESSURE DROP (SI)

COOLER KEY

CODE MODEL

H YCAJ110, 120, 130

UNIT POWER MIN. MAX.

200-3-60 180 220

230-3-60 207 253

380-3-60 355 415

460-3-60 414 506

380/415-3-50 342 440

346-3-50 311 381

575-3-60 517 633

MODELLVG.WATER COOLER AIR ON

YCATEMP. °C FLOW CONDENSER °C

MIN.1 MAX. MIN. MAX. MIN.2 MAX.3

J110 4.4 10 9.5 40.4 -17.8 54.4

J120 4.4 10 9.5 40.4 -17.8 54.4

J130 4.4 10 9.5 40.4 -17.8 54.4

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(ENGLISH)

PHYSICAL DATA

MODEL60 HZ J110 J120 J130

YCANOMINAL CAPACITY (TONS) 104.7 112.2 119.6NO. OF REFRIG. CIRCUITS 2 2 2

SYS. 1JG43-M JG44-P JG44-P

COMPRESSOR MODEL (60 HP) (80 HP) (80 HP)& MOTOR HORSEPOWER

SYS. 2JG43-M JG43-M JG44-P(60 HP) (45 HP) (80 HP)

UNIT CAPACITY CONTROL 5 Steps 5 Steps 5 Steps

CONDENSER – DWP 450 PSIG6 6 6

NO. OF FANS (42"Dia. Direct Drive)HP/kW Each 1140 RPM 5/2.9 5/2.9 5/2.9TOTAL AIRFLOW (CFM) 88,533 88,533 88,533COOLER – DUAL CIRCUITED

DWP – 235 PSIG REF. SIDE,150 PSIG WATER SIDE

16" x 8' 16" x 8' 16" x 8'

DIA. X LENGTHWATER VOLUME (GALS.) 48 48 48

GPMMIN. 150 150 150MAX. 640 640 640

SHIPPINGAlum. Fins 11,489 11,539 11,639

WEIGHT (LBS.)Copper Fins 13,197 13,297 13,447

OPERATINGAlum. Fins 11,889 11,989 12,089Copper Fins 13,597 13,747 13,897

REFRIG. CHARGE (LBS. R-22)Sys. 1 108 115 125Sys. 2 121 128 140

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(SI)

PHYSICAL DATA

MODEL60 HZ J110 J120 J130

YCANOMINAL CAPACITY (KW) 368.3 394.5 420.7NO. OF REFRIG. CIRCUITS 2 2 2

SYS. 1JG43-M JG44-P JG44-P

COMPRESSOR MODEL (44 KW) (59 KW) (59 KW)& MOTOR KW

SYS. 2JG43-M JG43-M JG44-P(44 kW) (33 kW) (59 kW)

UNIT CAPACITY CONTROL 5 Steps 5 Steps 5 Steps

CONDENSER – DWP 3 kPa6 6 6

NO. OF FANS (1066 mm Dia. Direct Drive)HP/kW Each 1140 RPM 5/3.7 5/2.9 5/2.9AIRFLOW TOTAL (L/S) 41,783 41,783 41,783COOLER – DUAL CIRCUITED

406 mm 406 mm 406 mmDWP – 1.62 kPa REF. SIDE,

x x x1.0 kPa WATER SIDE

2438 mm 2438 mm 2438 mmDIA. X LENGTHWATER VOLUME (L) 182 182 182

L/SEC.MIN. 9.5 9.5 9.5MAX. 40.4 40.4 40.4

SHIPPINGAlum. Fins 5211 5234 5079

WEIGHT (Kg)Copper Fins 5986 6031 6099

OPERATINGAlum. Fins 5393 5438 5483Copper Fins 6167 6236 6304

REFRIG. CHARGE (Kg R-22)Sys. 1 49 52 57Sys. 2 55 58 64

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DIMENSIONS(English)

LD01337

LD01334

LD01335

LD01336

NOTES:

1. Clearances Recommended YORK clearances for peak performance, reliable operation, and maintenance:Side to wall 8'; Rear to wall 8'; Control panel end to wall 5'; Over the top no obstructions allowed; Two units side by side 12',(walls should be no higher than the unit). The area within the clearances and under the unit(s) must be kept clean of clutter. Additional heightshould be included to allow for snow accumulation for units which are expected to operate at full load during the winter. Reducedclearances may be used due to jobsite restrictions. The unit(s) with optional controls will allow optimal operation preventing the condenserpressure from exceeding the maximum limit. The units will continue to operate without nuisance high pressure cutout even though theairflow may be restricted at these conditions.

2. Panel bottom to be punched in field to accommodate power wiring conduit.

3. Use of isolators (optional) will increase height of unit approximately 6".

4. Drawings not to scale and are for planning purposes only. Contact nearest YORK Sales Office for detailed drawings.

See page 18 for 110 - 130 Ton Unit Isolator Selection.

WEIGHT DISTRIBUTION (LBS.)WATERCONN.

MODEL YCAA B C D E F

INLET/OUTLETDIA. (INCHES)

J110 1559 1936 2312 1544 1917 2290 8J120 1559 1936 2312 1544 1917 2290 8J130 1559 1936 2312 1544 1917 2290 8

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DIMENSIONS(SI)

WEIGHT DISTRIBUTION (Kg)WATERCONN.

MODEL YCAA B C D E F

INLET/OUTLETDIA. (INCHES)

J110 707 878 1049 700 870 1039 8J120 707 878 1049 700 870 1039 8J130 707 878 1049 700 870 1039 8

NOTES:

1. Clearances Recommended YORK clearances for peak performance, reliable operation, and maintenance:Side to wall 2440 mm; Rear to wall 2440 mm; Control panel end to wall 1525 mm; Over the top no obstructions allowed; Twounits side by side 3660 mm, (walls should be no higher than the unit). The area within the clearances and under the unit(s) must be keptclean of clutter. Additional height should be included to allow for snow accumulation for units which are expected to operate at full loadduring the winter. Reduced clearances may be used due to jobsite restrictions. The unit(s) with optional controls will allow optimal operationpreventing the condenser pressure from exceeding the maximum limit. The units will continue to operate without nuisance high pressurecutout even though the airflow may be restricted at these conditions.

2. Panel bottom to be punched in field to accommodate power wiring conduit.

3. Use of isolators (optional) will increase height of unit approximately 152 mm.

4. Drawings not to scale and are for planning purposes only. Contact nearest YORK Sales Office for detailed drawings.

See page 18 for 387 - 458 kW Unit Isolator Selection.

LD01332

LD01330

LD01333 LD01331

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DUAL COMPRESSOR POWER SUPPLY WIRING (STANDARD)

SYSTEM #1 WIRING SYSTEM #2 WIRING

MODEL MIN2 COND. MIN2 COND.YCA

MCA1

DUAL ELEMNF CKT BKR 4 INCOMING CPR CPR FAN MCA1

DUAL ELEMNF CKT BKR 4 INCOMING CPR CPR FANFUSE

DISC WIRE RANGE5RLA LRA 8 FLA

FUSEDISC WIRE RANGE5

RLA LRA 8 FLA

MIN.3 MAX.3 SW MIN MAX(CU ONLY) EACH MIN.3 MAX.3 SW MIN MAX

(CU ONLY) EACH

J110 -17 295 350 500 400 350 450 (2) #6 - 250 212 803 10.0 295 350 500 400 350 450 (2) #6 - 250 212 803 10.0J110 -28 267 350 450 400 350 400 (2) #6 - 250 184 698 12.0 267 350 450 400 350 400 (2) #6 - 250 184 698 12.0J110 -40 162 200 250 200 200 250 (2) #6 - 250 116 441 5.2 162 200 250 200 200 250 (2) #6 - 250 116 441 5.2

J110 -46 131 175 200 200 175 200 (2) #6 - 250 92 349 5.0 131 175 200 200 175 200 (2) #6 - 250 92 349 5.0J110 -58 107 150 175 200 150 150 (2) #6 - 250 74 279 4.9 107 150 175 200 150 150 (2) #6 - 250 74 279 4.9J120 -17 368 450 600 400 450 600 (2) #6 - 250 270 1063 10.0 295 350 500 400 350 450 (2) #6 - 250 212 803 10.0

J120 -28 330 400 500 400 400 500 (2) #6 - 250 235 924 12.0 267 350 450 400 350 400 (2) #6 - 250 184 698 12.0J120 -40 201 250 300 200 250 300 (2) #6 - 250 148 584 5.2 162 200 250 200 200 250 (2) #6 - 250 116 441 5.2J120 -46 162 200 250 200 200 250 (2) #6 - 250 117 462 5.0 131 175 200 200 175 200 (2) #6 - 250 92 349 5.0

J120 -58 132 175 225 200 175 200 (2) #6 - 250 94 370 4.9 107 150 175 200 150 150 (2) #6 - 250 74 279 4.9J130 -17 368 450 600 400 450 600 (2) #6 - 250 270 1063 10.0 368 450 600 400 450 600 (2) #6 - 250 270 1063 10.0J130 -28 330 400 500 400 400 500 (2) #6 - 250 235 924 12.0 330 400 500 400 400 500 (2) #6 - 250 235 924 12.0

J130 -40 201 250 300 200 250 300 (2) #6 - 250 148 584 5.2 201 250 300 200 250 300 (2) #6 - 250 148 584 5.2J130 -46 162 200 250 200 200 250 (2) #6 - 250 117 462 5.0 162 200 250 200 200 250 (2) #6 - 250 117 462 5.0J130 -58 132 175 225 200 175 200 (2) #6 - 250 94 370 4.9 133 175 225 200 175 200 (2) #6 - 250 94 370 4.9

ELECTRICAL DATA

NOTES for Electrical Data, pages 3 - 6:

1. Minimum circuit ampacity (MCA) is based on 125% of the rated load amps for the largest motor plus 100% of the rated load amps for allother loads included in the circuit, per N.E.C. Article 430-24. If a Factory Mounted Control Transformer is provided, add the following tothe system #1 MCA values in the YCA Tables: -17, add 10 amps; -28, add 9 amps; -40, add 5 amps; -46, add 4 amps; -58, add 3 amps.

2. Minimum Non-Fused Disconnect Switch size is based on a minimum of 115% of the sum of the RLAs for all the loads included in the circuit,per N.E.C. 440-12A1. Available as factory-mounted option on units with single-point power supply.

3. Minimum Dual Element Fuse size is based on 150% of the largest motor RLA plus 100% of the remaining RLAs. (U.L. Standard 1995,Section 36.1) Maximum Dual Element Fuse size is based on 225% of the maximum RLA plus 100% of the RLAs for all other loads includedin the circuit, per N.E.C. 440-22. Minimum fuse rating = 1.5 x Largest Compr RLA + Other Compr RLAs + (# fans) x Fan FLA. Maximumfuse rating = 2.25 x Largest Compr RLA + Other Compr RLAs + (# Fans) x Fan FLA. These sizes are for field-supplied fuses.

4. Minimum and Maximum Circuit Breaker rating required per N.E.C. and U.L. 1995 Fig. 36.2. Minimum C.B. rating = 1.5 x Largest Compr RLA+ Other Compr RLAs + (# Fans) x Fan FLA. Maximum C.B. rating = 2.25 x Largest Compr RLA + Other Compr RLAs + (# Fans) x Fan FLA.

5. Wire Range is the minimum and maximum wire size that can be accommodated by the unit wiring lugs. The (1), (2), or (3) preceding thewire range indicates the number of termination points available per phase. The (1-2) preceding the wire range indicates that a singledouble-barreled lug is available per phase that can accept up to two wires of the wire range specified. (1) #1-600 or (2) #1-250indicates that a single lug is supplied and it will accept a single wire up to 600MCM or 2 wires up to 250MCM. Actual wire size and numberof wires per phase must be determined based on ampacity and job requirements using N.E.C. wire sizing information. The aboverecommendations are based on the National Electrical Code and using copper connectors only. Field wiring must also comply with localcodes.

6. A ground lug is provided for each compr. system to accommodate field grounding conductor per N.E.C. Article 250-54. A control circuitgrounding lug is also supplied. Incoming ground wire range is #6 - 350 MCM (104 - 220 Tons)(334 - 810 kW).

7. The supplied disconnect is a Disconnecting Means as defined in N.E.C. 100.B, and is intended for isolating the unit from the availablepower supply to perform maintenance and troubleshooting. This disconnect is not intended to be a Load Break Device.

8. All unit compressors have a part winding electrical configuration such that the indicated Locked Rotor Amps are Part Wind Locked RotorAmps. YCAJ110 - 130 models have part-wind start as standard.

DUAL COMPRESSOR POWER SUPPLY WIRING STANDARD UNIT

2L32L22L1G2L 1L1 1L2 1L3

G G

SYS 1POWERSUPPLY

SYS 2POWERSUPPLY

BY OTHERS

115-1-60CONTROL

POWERSUPPLY

SYS.1TERMINALS

SYS.2TERMINALS

UNIT PANELS

LD01173

SEE NOTE 5

SEE NOTE 5

SEE NOTE 6

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SINGLE POINT POWER SUPPLY WIRING (OPTIONAL)

SYSTEM #1 SYSTEM #2

MODEL MIN2

YCA MCA1DUAL ELEM NF

INCOMING YORK SUPPLIED DISCONNECTCPR CPR FAN CPR CPR FANFUSE

DISCWIRE RANGE5

(CU ONLY)RLA LRA 8 FLA RLA LRA 8 FLA

MIN.3 MAX.3 SW(CU ONLY)

J110 -46 238 300 300 400 (2) #2 - 600 (1) #1 - 600 or (2) #1 - 250 92 349 5.0 92 349 5.0

J110 -58 196 225 250 400 (2) #2 - 600 (1) #1 - 600 or (2) #1 - 250 74 279 4.9 74 279 4.9J120 -46 269 300 350 400 (2) #2 - 600 (1) #1 - 600 or (2) #1 - 250 117 462 5.0 92 349 5.0J120 -58 221 250 300 400 (2) #2 - 600 (1) #1 - 600 or (2) #1 - 250 94 370 4.9 74 279 4.9

J130 -46 294 350 400 400 (2) #2 - 600 (1) #1 - 600 or (2) #1 - 250 117 462 5.0 117 462 5.0J130 -58 241 300 300 400 (2) #2 - 600 (1) #1 - 600 or (2) #1 - 250 94 370 4.9 94 370 4.9

POWER SUPPLY WIRING FACTORY DISCONNECT SWITCHES AND FUSES

FACTORY MOUNTED SYSTEM #1 SYSTEM #2

MODELMIN2

DISCONNECT SWITCH COND. COND.YCA MCA1

DUAL ELEM NF CKT BKR 4INCOMING

FACT. MTD.CPR CPR FAN

FACT. MTD.CPR CPR FANFUSE

DISCWIRE RANGE5

FUSE RLA LRA 8 FLA FUSE RLA LRA 8 FLA

MIN.3 MAX.3SW

MIN MAX (CU ONLY) MIN 3 MAX3 EACH MIN3 MAX3 EACH

J110 -17 537 600 700 600 600 700 (3) 3/0 - 500 350 500 212 1005 10.0 350 500 212 1005 10.0J110 -28 487 600 600 600 600 600 (3) 3/0 - 500 350 450 184 874 12.0 350 450 184 874 12.0

J110 -40 293 350 400 400 350 400 (1) #1 - 600 or (2) #1 - 250 200 250 116 552 5.2 200 250 116 552 5.2J110 -46 238 300 300 400 300 300 (1) #1 - 600 or (2) #1 - 250 175 200 92 437 5.0 175 200 92 437 5.0J110 -58 196 225 250 400 225 250 (1) #1 - 600 or (2) #1 - 250 150 175 74 350 4.9 150 175 74 350 4.9

J120 -17 610 700 800 800 700 800 (3) 3/0 - 500 450 600 270 1332 10.0 350 500 212 1005 10.0J120 -28 550 700 700 600 700 700 (3) 3/0 - 500 400 500 235 1158 12.0 350 450 184 874 12.0J120 -40 333 400 450 400 400 450 (1) #1 - 600 or (2) #1 - 250 250 300 148 731 5.2 200 250 116 552 5.2

J120 -46 269 300 350 400 300 350 (1) #1 - 600 or (2) #1 - 250 200 250 117 579 5.0 175 200 92 437 5.0J120 -58 221 250 300 400 250 300 (1) #1 - 600 or (2) #1 - 250 175 225 94 463 4.9 150 175 74 350 4.9J130 -17 668 800 800 800 800 800 (3) 3/0 - 500 450 600 270 1332 10.0 450 600 270 1332 10.0

J130 -28 600 700 800 800 700 800 (3) 3/0 - 500 400 500 235 1158 12.0 400 500 235 1158 12.0J130 -40 365 450 500 400 450 500 (1) #1 - 600 or (2) #1 - 250 250 300 148 731 5.2 250 300 148 731 5.2J130 -46 294 350 400 400 350 400 (1) #1 - 600 or (2) #1 - 250 200 250 117 579 5.0 200 250 117 579 5.0

J130 -58 241 300 300 400 300 300 (1) #1 - 600 or (2) #1 - 250 175 225 94 463 4.9 175 225 94 463 4.9

See page 3 for notes.

LEGEND:

VOLT = VoltageMCA = Minimum Circuit AmpacityDISC = DisconnectN/A = Not AvailableCPR-RLA = Compressor Running Load AmpsCPR-RLA = Compressor Part Winding Inrush AmpsFLA = Full Load AmpsCKT BRK = Circuit BreakerHACR = Heating, Air Conditioning and Refrigeration

DISCONNECT OPTION

SEE NOTE 5LD1174(R)

UNIT PANEL

G2L 2L32L22L1 1L1 1L2 1L3

BY OTHERS

CONTROLPOWERSUPPLY

OPTIONALFACTORY-MOUNTED

FUSES

GR

D

GR

DL1 L3L2

Page 14: Millennium LIQUID CHILLERS AIR-COOLED – …

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See page 3 for notes.

POWER SUPPLY WIRING SINGLE POINT WITH FACTORY UNIT MOUNTED CIRCUIT BREAKERS

SYSTEM #1 SYSTEM #2

MODELMIN2

INCOMING COND. COND.YCA MCA1

DUAL ELEM NF CKT BKR 4WIRE RANGE5

FACT. MTD.CPR CPR FAN

FACT. MTD.CPR CPR FANFUSE

DISC(CU ONLY)

FUSE RLA LRA 8 FLA FUSE RLA LRA 8 FLA

MIN.3 MAX.3SW

MIN MAX MIN3 MAX3 EACH MIN3 MAX3 EACH

J110 -17 537 600 700 600 600 700 (3) 3/0 - 500 350 450 212 1005 10.0 350 450 212 1005 10.0

J110 -28 487 600 600 600 600 600 (1) #1 - 600 or (2) #1 - 250 350 400 184 874 12.0 350 400 184 874 12.0J110 -40 293 350 400 400 350 400 (1) #1 - 600 or (2) #1 - 250 200 250 116 552 5.2 200 250 116 552 5.2J110 -46 238 300 300 400 300 300 (1) #1 - 600 or (2) #1 - 250 175 200 92 437 5.0 175 200 92 437 5.0

J110 -58 196 225 250 400 225 250 (1) #1 - 600 or (2) #1 - 250 150 150 74 350 4.9 150 150 74 350 4.9J120 -17 610 700 800 800 700 800 (3) 3/0 - 500 450 600 270 1332 10.0 350 450 212 1005 10.0J120 -28 550 700 700 600 700 700 (3) 3/0 - 500 400 500 235 1158 12.0 350 400 184 874 12.0

J120 -40 333 400 450 400 400 450 (1) #1 - 600 or (2) #1 - 250 250 300 148 731 5.2 200 250 116 552 5.2J120 -46 269 300 350 400 300 350 (1) #1 - 600 or (2) #1 - 250 200 250 117 579 5.0 175 200 92 437 5.0J120 -58 221 250 300 400 250 300 (1) #1 - 600 or (2) #1 - 250 175 200 94 463 4.9 150 150 74 350 4.9

J130 -17 668 800 800 800 800 800 (3) 3/0 - 500 450 600 270 1332 10.0 450 600 270 1332 10.0J130 -28 600 700 800 800 700 800 (3) 3/0 - 500 400 500 235 1158 12.0 400 500 235 1158 12.0J130 -40 365 450 500 400 450 500 (1) #1 - 600 or (2) #1 - 250 250 300 148 731 5.2 250 300 148 731 5.2

J130 -46 294 350 400 400 350 400 (1) #1 - 600 or (2) #1 - 250 200 250 117 579 5.0 200 250 117 579 5.0J130 -58 241 300 300 400 300 300 (1) #1 - 600 or (2) #1 - 250 175 200 94 463 4.9 175 200 94 463 4.9

L 2 G 2L1 2L2 2L3 1L1 1L2 1L3

GR

D

GR

D

BY OTHERS

CONTROLPOWERSUPPLY

COMPRESSORPOWERSUPPLY

SINGLE POINT WITH FACTORY MOUNTEDCIRCUIT BREAKERS

LD01556(R)

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G2L 2L32L22L1

L1 L2 L3

1L1 1L2 1L3

G G

115-1-60CONTROL

POWERSUPPLY

UNIT PANEL

COMPRESSORPOWERSUPPLYBY OTHERS

CONTROL POWER SUPPLY

MAXIMUM NON-FUSEDUNIT CONTROL MINIMUM DUAL- DISC.

VOLTAGE POWER CIRCUIT ELEMENT SWITCHSUPPLY AMPACITY FUSE SIZE SIZE

StandardModels without 115-1-60 20A 20A, 250V 30A, 240V

Transformers

LD01175

SEE NOTE 6 (TYP)

SEE NOTE 5

LEGEND:

VOLT = VoltageMCA = Minimum Circuit AmpacityDISC = DisconnectN/A = Not AvailableCPR-RLA = Compressor Running Load AmpsCPR-RLA = Compressor Part Winding Inrush AmpsFLA = Full Load AmpsCKT BRK = Circuit BreakerHACR = Heating, Air Conditioning and Refrigeration

SINGLE POINT OPTION

See page 3 for notes.

Page 16: Millennium LIQUID CHILLERS AIR-COOLED – …

16 YORK INTERNATIONAL

INSTALLATION

WARNING:

To protect warranty, this equipment must be in-stalled and serviced by an authorized YORK ser-vice mechanic or a qualified service person experi-enced in chiller installation. Installation must com-ply with all applicable codes, particularly in regardto electrical wiring and other safety elements suchas relief valves, HP cutout settings, design work-ing pressures and ventilation requirements consis-tent with the amount and type of refrigerant charge.

Lethal voltages exist within the control panel. Be-fore servicing, open and tag all disconnect switches.

FIG. 4 RIGGING THE CHILLER

INSTALLATION CHECKLIST

The following items, 1 thru 5, must be checked beforeplacing units into operation.

1. Inspect unit for shipping damage.

2. Rig unit per Fig. 4. Remove unpainted shipping bracesafter installation.

3. Open unit only to install water piping system. Do notremove protective covers from water connections untilpiping is ready for attachment. Check water piping toinsure cleanliness.

4. Pipe unit using good piping practice and consistentwith local code requirements.

5. Check to see that unit is installed and operated withinLIMITATIONS shown on pages 7 and 8.

The following pages outline procedures to be followed.

HANDLING

These units are shipped as completely assembled unitscontaining full operating charge, and care should be takento avoid damage due to rough handling.

The units are shipped without export crating unless it isspecified by Sales Order.

A unit should be lifted by inserting hooks through theholes provided in unit base rails. Spreader bars shouldbe used to avoid crushing the unit with the lifting chains.(See Fig. 4).

28694A(R)

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FORM 150.60-NM5

17YORK INTERNATIONAL

25112A

FIG. 5 COMPRESSOR MOUNTING PAD

COMPRESSOR MOUNTING PAD

INSPECTION

Immediately upon receiving the unit, it should be in-spected for possible damage which may have occurredduring transit. If damage is evident, it should be noted onthe carriers freight bill. A written request for inspectionby the carriers agent should be made at once. See In-struction 50.15-NM for more information and details.

LOCATION AND CLEARANCES

These units are designed for outdoor installations onground level, rooftop, or beside a building. The locationshould be selected for minimum sun exposure and toinsure an adequate supply of fresh air for the condenser.The units must be installed with sufficient clearances forair entrance to the condenser coil, for air discharge awayfrom the condenser, and for servicing access.

In installations where winter operation is intended andsnow accumulations are expected, additional height mustbe provided to insure normal condenser air flow. (SeeDIMENSIONS).

FOUNDATION

The unit should be mounted on a flat and level founda-tion, floor or rooftop, capable of supporting the entireoperating weight of the equipment. See PHYSICAL DATAfor operating weight. If the unit is elevated beyond thenormal reach of service personnel, a suitable catwalkmust be constructed around the unit. The catwalk mustbe capable of supporting service personnel, their equip-ment, and the reciprocating compressors.

Ground Level Locations

It is important that the units be installed on a substantialbase that will not settle. A one piece concrete slab withfooters extended below the frost line is highly recom-mended. Additionally, the slab should not be tied to themain building foundations as noise and vibration may betransmitted.

Mounting holes are provided in the steel channel for bolt-ing the unit to its foundation. (See DIMENSIONS).

For ground level installations, precautions should be takento protect the unit from tampering by or injury to unau-thorized persons. Screws and/or latches on access pan-els will prevent casual tampering. However, further safetyprecautions such as a fenced-in enclosure or lockingdevices on the panels may be advisable. A tamperproofkit is available as an option. Check local authorities forsafety regulations.

Rooftop Locations

Choose a spot with adequate structural strength to safelysupport the entire weight of the unit and service person-nel. Care must be taken not to damage the roof.

Consult the building contractor or architect if the roof is

bonded. Roof installations should have wooden beams(treated to reduce deterioration), cork, rubber or vibra-tion isolators under the base to minimize vibration.

SHIPPING BRACES

Two shipping brackets (typically galvanized steel) whichrun diagonally along each side of the unit, must be re-moved once the unit is mounted on its foundation. Athird bracket on the right rear of the unit should also beremoved. This bracket runs across the bottom right cor-ner of the unit behind the compressors.

SPRING ISOLATORS (OPTIONAL)

When ordered, six (6) spring isolators will be furnished.

1. Identify isolator and locate at proper mounting pointusing table on page 18.

2. Block up equipment so as to install spring mountswith pin on top of housing into Equipment MountingHoles.

3. Mounting Adjust Nut is inside the isolator mount lo-cated just below the top plate of the mount. Turn nut2 turns clockwise (down) to load spring mount at eachlocation.

4. Take two additional turns on Adjustment Nut of eachlocation.

5. Repeat step No. 3 as many times as necessary tobring height of isolator to proper height.

6. Take additional turns on mounts at low side or cornerto level the equipment.

COMPRESSOR MOUNTING

The compressors are mounted on four (4) isolator pads(one under each compressor foot). (See Fig. 5). The mount-ing bolts are not to be loosened or adjusted at installation.

Page 18: Millennium LIQUID CHILLERS AIR-COOLED – …

18 YORK INTERNATIONAL

WEIGHT DISTRIBUTION AND ISOLATOR LOCATIONS FOR EACH MODEL

VMC CP-2-X

LD01089

NOTE: Standard 1" deflection isolator drawings. Consult your nearest YORK representative for additional isolator options.

MODEL A B C D E FYCAJ110 CP-2-28 CP-2-31 CP-2-32 CP-2-28 CP-2-31 CP-2-32YCAJ120 CP-2-28 CP-2-31 CP-2-32 CP-2-28 CP-2-31 CP-2-32

YCAJ130 CP-2-28 CP-2-31 CP-2-32 CP-2-28 CP-2-31 CP-2-32

ISOLATOR LOCATIONS (95 - 130 TONS [335 - 458 kW])

WEIGHT DISTRIBUTION (LBS.)WATERCONN.

MODEL YCAA B C D E F

INLET/OUTLETDIA. (INCHES)

J110 1559 1936 2312 1544 1917 2290 8J120 1559 1936 2312 1544 1917 2290 8

J130 1559 1936 2312 1544 1917 2290 8

LD02957

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FORM 150.60-NM5

19YORK INTERNATIONAL

CHILLED LIQUID PIPING

GENERAL When the unit has been located in its finalposition, the unit liquid piping may be connected. Nor-mal installation precautions should be observed in orderto receive maximum operating efficiencies. Piping shouldbe kept free of all foreign matter. All liquid cooler pipingmust comply in all respects with local plumbing codesand ordinances.

Since elbows, tees and valves decrease pump capacity,all piping should be kept as simple as possible.

Hand stop valve should be installed in all lines to facili-tate servicing.

Piping to the inlet and outlet connections of the chillershould include high-pressure rubber hose or piping loopsto insure against transmission of water pump vibration.This is optional and the necessary components must beobtained in the field.

Drain connections should be provided at all low points topermit complete drainage of liquid cooler and piping sys-tem.

A small valve or valves should be installed at the highestpoint or points in the chilled liquid piping to allow anytrapped air to be purged. Vent and drain connectionsshould be extended beyond the insulation to make themaccessible.

The piping to and from the cooler must be designed tosuit the individual installation. It is important that thefollowing considerations be observed:

1. The chilled liquid piping system should be laid out sothat the circulating pump discharges directly into thecooler. The suction for this pump should be taken fromthe piping system return line and not the cooler.

2. The inlet and outlet cooler liquid connection sizes aregiven on pages 10 and 11.

3. A strainer, preferably 40 mesh, MUST be installed inthe cooler inlet line just ahead of the cooler.

4. All chilled liquid piping should be thoroughly flushedto free it from foreign material before the system isplaced into operation. Use care not to flush any for-eign material into or through the cooler.

5. As an aid to servicing, thermometers and pressuregauges should be installed in the inlet and outlet wa-ter lines. One connection point (plugged) is providedin each cooler nozzle. Thermometers and gauges arenot furnished with the unit and are to be furnished byother suppliers.

6. The chilled liquid lines that are exposed to outdoorambients should be wrapped with a supplementalheater cable and insulated to protect against freeze-up during low ambient periods, and to prevent forma-tion of condensation on lines in warm humid climates.

7. A chilled water flow switch, (either by YORK or oth-

ers) MUST be installed in the leaving water piping ofthe cooler. There should be a straight horizontal runof at least 5 diameters on each side of the switch.Adjust the flow switch paddle to the size of pipe inwhich it is to be installed. (See manufacturers in-structions furnished with switch). The switch is to bewired to terminals in the control panel as shown inthe WIRING DIAGRAM (pages 20 - 28).

WARNING: Flow switch must not be used to stop andstart chilier. It is intended only as a safetyswitch.

COMPRESSOR INSULATION

In high humidity environments, compressor sweating maybe noted. In most applications, this is of no concern. How-ever, if it is undesirable, it is the responsibility of the in-staller to make provisions to field insulate the compressoror install a factory insulation kit when they become avail-able. Contact YORK Factory Marketing for availability.

ELECTRICAL WIRING

Liquid Chillers are shipped with all factory mounted con-trols wired for operation.

Field Wiring Power wiring must be provided througha fused disconnect switch to the unit terminals (or op-tional molded case disconnect switch) in accordancewith N.E.C. or local code requirements. Minimum circuitampacity and maximum dual element fuse size are givenon pages 12 - 15. A 115-1-60/50, 20 amp source mustbe supplied for the control panel through a fused discon-nect when a control panel transformer (optional) is notprovided. Refer to WIRING DIAGRAM (pages 20 - 28).

Affiliated apparatus, such as a chilled water flow switch,auxiliary contacts from the chilled water pump starter,alarms, etc., should be interlocked into the control panelcircuit. These field modifications may be made as shownon the WIRING DIAGRAM (pages 20 - 28).

MULTIPLE UNITS

For increased compressor protection and to reduce powerinrush at start-up on multiple chiller installations, provi-sions must be made to prevent simultaneous startup oftwo or more units. Also, some method must be employedto automatically cycle one or more of the units on or offto permit more efficient operation at part load conditions.A sequencing kit may be acquired through your localYORK representative.

RELIEF VALVES

An internal relief valve(s) is installed internally in eachcompressor. A second integral internal relief valve isbuilt into the liquid line solenoid valve of each system.All relief valves are resealable type safety devices.

Page 20: Millennium LIQUID CHILLERS AIR-COOLED – …

20 YORK INTERNATIONAL

YCAJ110 - 130 WIRING DIAGRAMELEMENTARY DIAGRAM

FIG. 6 – ELEMENTARY DIAGRAM

LEGEND

Transient Voltage Suppression

Terminal Block for Customer Connections

Terminal Block for Customer Low Voltage(Class 2) Connections. See Note 2

Terminal Block for YORK Connections Only

Wiring and Components by YORK

Optional Equipment

Wiring and/or Components by Others

T S

NOTES:

1. Field wiring to be in accordance with the current edition of theNational Electrical Code as well as all other applicable codes andspecifications.

2. Contacts must be suitable for switching 24VDC, (gold contactsrecommended). Wiring shall not be run in the same conduit withany line voltage wiring.

3. To cycle unit on and off automatically with contact shown, installa cycling device in series with the flow switch (FLSW). See Note2 for contact rating and wiring specifications. Also refer to cau-tions on the following page.

4. To stop unit (Emergency Stop) with contacts other than thoseshown, install the stop contact between terminals 5 and 1. If astop device is not installed, a jumper must be connected be-tween terminals 5 and 1. Device must have a minimum contactrating of 100VA at 115 volts A.C.

5. Contacts are rated at 115V, 100VA, resistive load only, and mustbe suppressed at load by user.

6. See Installation, Operation and Maintenance Manual.

7. Power factor correction capacitors may be installed on the chillerelectrical system (as shown) as a factory installed option.

8. Jumper installed for simultaneous operation of condenser fans 5& 6.

LD02222

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FORM 150.60-NM5

21YORK INTERNATIONAL

LD02223

FIG. 6 – ELEMENTARY DIAGRAM (Cont’d)

Page 22: Millennium LIQUID CHILLERS AIR-COOLED – …

22 YORK INTERNATIONAL

ELEMENTARY DIAGRAM

Page 23: Millennium LIQUID CHILLERS AIR-COOLED – …

FO

RM

150.6

0-N

M5

23Y

OR

K IN

TE

RN

AT

ION

AL

CAUTION:No Controls (relays,etc.) should bemounted in the SmartPanel enclosure orconnected to powersupplies in the controlpanel. Additionally, con-trol wiring not con-nected to the SmartPanel should not be runthrough the cabinet.This could result in nui-sance faults.

CAUTION:Any inductive devices(relays) wired in serieswith the flow switch forstart/stop, into theAlarm circuitry, or pilotrelays for pump start-ers wired through mo-tor contactor auxiliarycontacts must be sup-pressed with YORKP/N 031-00808-000suppressor across therelay/contactor coil.

Any contacts con-nected to flow switchinputs or BAS inputs onterminals 13 - 19 orTB3, or any other ter-minals, must be sup-pressed with a YORKP/N 031-00808-000suppressor across therelay/contactor coil.

CAUTION:Control wiring con-nected to the controlpanel should never berun in the same con-duit with power wiring.

FIG. 6 – ELEMENTARY DIAGRAM (Cont’d)

CONTROL POWER SUPPLY

MAXIMUM NON-FUSEDUNIT CONTROL MINIMUM DUAL- DISC.

VOLTAGE POWER CIRCUIT ELEMENT SWITCHSUPPLY AMPACITY FUSE SIZE SIZE

StandardModels without 115-1-60 20A 20A, 250V 30A, 240VTransformers

LD02221

Page 24: Millennium LIQUID CHILLERS AIR-COOLED – …

24 YORK INTERNATIONAL

LD0224FIG. 7 CONNECTION DIAGRAM

CONNECTION DIAGRAM

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FORM 150.60-NM5

25YORK INTERNATIONAL

LD02225FIG. 7 CONNECTION DIAGRAM (Contd)

Page 26: Millennium LIQUID CHILLERS AIR-COOLED – …

26 YORK INTERNATIONAL

CONNECTION DIAGRAMTERMINAL BOX AND SYSTEM WIRING

FIG. 8 SYSTEM WIRING

LD02697

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FORM 150.60-NM5

27YORK INTERNATIONAL

CONNECTION DIAGRAMTERMINAL BOX AND SYSTEM WIRING

FIG. 8 SYSTEM WIRING (Contd)

LD02698

Page 28: Millennium LIQUID CHILLERS AIR-COOLED – …

28 YORK INTERNATIONAL

YCAJ110 - 130 CONNECTION DIAGRAMTERMINAL BOX AND SYSTEM WIRING

FIG. 8 SYSTEM WIRING (Contd)

LD02226

Page 29: Millennium LIQUID CHILLERS AIR-COOLED – …

FORM 150.60-NM5

29YORK INTERNATIONAL

UNIT CONTROLS AND OPERATIONYORK MILLENNIUM CONTROL CENTER

FIG. 9 CONTROL CENTER KEYPAD

INTRODUCTION

The YORK Millennium Control Center is a microproces-sor based control system capable of multi-circuit controlto maintain chilled liquid temperature.

A 40 character display (2 lines of 20 characters) allowsthe operator to display system operating parameters aswell as access programmed information already inmemory. A keypad for programming and accessing set-points, pressures, temperatures, motor current, cutouts,daily schedule, options, and fault information is provided.

A master ON/OFF switch is available to activate or de-activate the chiller system. Separate system (SYS)switches for each refrigerant system (up to 4) are pro-vided on the Microprocessor Board.

Remote cycling, unloading, and chilled water tempera-ture reset can be accomplished by user supplied drycontacts.

Compressor starting/stopping and loading/unloading de-cisions are performed by the Microprocessor to main-tain leaving water temperatures. These decisions are afunction of temperature deviation from setpoint and rateof change of temperature.

MICROPROCESSOR BOARD

The Microprocessor Board is the controller and decision-maker in the control panel. System inputs from pres-sure transducers, temperature sensors, and C.T.s areconnected directly to the Microprocessor Board. The Mi-croprocessor Board circuitry multiplexes these analoginputs, digitizes them, and constantly scans them tokeep a constant watch on the chiller operating condi-tions. From this information, the Microprocessor thenissues commands to the Relay Output Board to controlcontactors, solenoids, etc. for water temperature con-trol and to react to safety conditions.

Keypad commands are acted upon by the micro tochange setpoints, cut-outs, scheduling, operating re-quirements, and to provide displays.

A +12V REG supply voltage from the Power Supply Boardis converted to +5V REG by a voltage regulator locatedon the Microprocessor Board. This voltage is used tooperate integrated circuitry on the board.

Four system switches located on the MicroprocessorBoard activate or deactivate the individual systems (com-pressors).

02711TG

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30 YORK INTERNATIONAL

28696A

FIG. 10 POWER PANEL

POWER SUPPLY BOARD

The on-board switching power supply converts 24VACfrom the 2T transformer to +12V REG which is suppliedto the Microprocessor Board, Relay Board, and 40 Char-acter Display to operate integrated circuitry.

A rectifier and filtering circuit for each motor current cir-cuit rectifies and filters these signals to variable DC.These signals are then fed to the Microprocessor Board.

RELAY OUTPUT BOARD

This board converts 0 - 12VDC logic level outputs fromthe Microprocessor Board to 120VAC levels used bymotor contactors, solenoid valves, etc. to control sys-tem operation. The common side of all relays on theRelay Output Board is converted to +12V REG.

The open collector outputs of the Microprocessor Boardenergize the DC relays by pulling the other side of therelay coil to ground. When not energized, both sides ofthe relay coils will be at +12VDC potential.

I/O EXPANSION BOARD

The I/O Expansion Board allows the Micro to receiveadditional analog inputs from Oil Temperature Sensorsand optional Discharge Temperature Sensors.

These inputs are multiplexed and sent to the micropro-cessor board to allow the micro to monitor these inputsfor display and as safeties.

CURRENT TRANSFORMER (C.T.)

A C.T. on the 3φ power wiring of each motor sends ACsignals proportional to motor current to the Power Sup-ply Board which rectifies and filters the signal to variableDC voltage (analog). This analog level is then fed to theMicroprocessor Board to allow it to monitor motor cur-rent.

40 CHARACTER DISPLAY

The 40 Character Display (2 lines of 20 characters) is aliquid crystal display used for displaying system param-eters and operator messages. The display has a lightedbackground for night viewing as well as a special featurewhich intensifies the display for viewing in direct sun-light.

KEYPAD

An operator keypad allows complete control of the sys-tem from a central location. The keypad offers a multi-tude of commands available to access displays, pro-gram setpoints, and initiate system commands.

BATTERY BACK-UP

The Microprocessor Board contains a Real Time Clockintegrated circuit chip with an internal battery back-up.The purpose of this battery back-up is to assure anyprogrammed values (setpoints, clock, cut-outs, etc.) arenot lost during a power failure regardless of the time in-volved in a power outage or shutdown period.

CURRENT TRANSFORMER

FANOVERLOADS

FANCONTACTORS

TB

TB1: CONNECTIONSFOR OPTIONAL

ALARMS, EVAP.PUMP, COND. PUMP,EMERG. STOP AND

L & 2 115VACCONTROL PANEL

SUPPLY

FANOVERLOADS

FANCONTACTORS

GROUNDLUG

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FORM 150.60-NM5

31YORK INTERNATIONAL

FIG. 11 CONTROL PANEL WITHOUT I/O EXPANSION PANEL

FIG. 12 CONTROL PANEL WITH I/O EXPANSION PANEL

28697A

LCD DISPLAYBOARD

MICROPROCESSORBOARD

UNIT ON/OFFSWITCH

POWERSUPPLYBOARD

2TTRANSFORMER

RELAYOUTPUTBOARD #1

LOCATIONOF OPTIONALRELAYOUTPUTBOARD #2

TB3CONNECTIONSFOR FLOWSWITCH,LEAD/LAGSELECT &EMS/BASCONTROLS

26000A

LCD DISPLAYBOARD

MICROPROCESSORBOARD

TB3CONNECTIONS FORFLOW SWITCH,AUXILLIARY CYCLING,LEAD/LAG SELECTOR& EMS/BAS CONTROLS

RELAY OUTPUTBOARD #2

RELAY OUTPUTBOARD #1

2T TRANSFORMER

POWER SUPPLYBOARDI /O EXPANSION

BOARD

Page 32: Millennium LIQUID CHILLERS AIR-COOLED – …

32 YORK INTERNATIONAL

Chilled Liquid Temps

A display indicating chiller leaving and return water tem-perature is provided when this push-button is pressed.

The minimum limit on the display is 8.7 DEG F. Themaximum limit on the display is 84.5 DEG F.

Ambient Temp

The outdoor ambient temperature is displayed when thispush-button is pressed.

The minimum limit on the display is 0 DEG F. Themaximum limit on the display is 133.8 DEG F.

System 1 Pressures

Oil pressure, suction pressure, and discharge* pressureon System 1 will be displayed when this push-button ispressed.

DISPLAY KEYS

L W T = 4 9 . 2 D E G F

R W T = 5 2 . 0 D E G F

CHILLEDLIQUID TEMPS

O U T S I D E A M B I E N T A I R

= 7 5 . 9 D E G F

AMBIENTTEMP

S Y S # 1 O I L = 7 2 P S I D

S P = 6 0 , D P = 2 2 9 P S I G

SYSTEM 1PRESSURES

DISPLAYKEYS

GENERAL

The DISPLAY keys allow the user to retrieve systempressures, system motor currents, chilled liquid tem-peratures, outdoor ambient temperature, compressorrunning times, number of compressor starts, and optioninformation on the chiller package. This data is useful formonitoring chiller operation, diagnosing potential futureproblems, troubleshooting, and commissioning the chiller.

Displayed data will be real-time data displayed on a 40character display consisting of 2 lines of 20 characters.The display will update all information at a rate of about2 seconds.

When a DISPLAY push-button is pressed, the corre-sponding message will be displayed and will remain onthe display until another push-button is pressed.

Display Messages may show characters indicatinggreater than (>) or less than (<). These charactersindicate the actual values are greater than or less thanthe limit values which are being displayed.

If a message is required to be updated faster than every2 seconds, the appropriate key for the desired displaymay be pushed and held. Updating will be at 0.4 secondintervals.

Each of the keys and an example of the typical corre-sponding display messages will be discussed in the textwhich follows.

* Discharge Pressure Readout is an option. Without this option, the display will read a fixed value.

02711TG

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FORM 150.60-NM5

33YORK INTERNATIONAL

on each compressor are also displayed. A total of 99999starts can be logged on a system before the counter willrollover.

The numbers 1 and 2 on the display message indi-cate compressor #1 and compressor #2.

These counters are zeroed at the factory or will indicateonly run time and number of starts logged during factorytesting at the time of shipment.

Options

The OPTIONS key provides a display of options whichhave been selected by the user. These options are se-lected by the S1 Dip Switch on the Microprocessor Board(Fig. 13). Proper programming of the switch is importantduring commissioning of the chiller. The OPTIONS dis-play allows a means of verifying the Dip Switch posi-tions without looking at or handling the MicroprocessorBoard. It also eliminates visual inspection of the some-times difficult to determine Dip Switch position.

When the OPTIONS key is pressed, the following mes-sage will first be displayed for 3 seconds:

8 Option Messages will then follow. Each will be dis-played for 3 seconds before the next display is auto-matically indexed. When all messages are displayed,the display message will automatically change to showa chiller STATUS message, just as if the STATUS keywas pressed.

Refer to Table 1 for a list of the displays and the corre-sponding switch positions in the order they appear. Twopossible messages may appear for each of the eightmessages depending on the Dip Switch position.

A detailed explanation of the meaning of each messageand a guide to programming the associated switch isprovided on pages 34 - 36.

Fig. 13 shows the location and verification of switch po-sitioning of S1.

The minimum limits are:

Oil Pressure: 0 PSID (0 bar)

Suction Pressure: 0 PSIG (0 bar)

Discharge Pressure: 0 PSIG (0 bar)

The maximum limits are:

Oil Pressure: 200 PSID (13.8 bar)

Suction Pressure: 200 PSIG (13.8 bar)

Discharge Pressure: 400 PSIG (27.6 bar)

System 2 Pressures

Oil pressure, suction pressure, and discharge pressureon System 2 will be displayed when this push-button ispressed.

The minimum limits are:

Oil Pressure: 0 PSID (0 bar)

Suction Pressure: 0 PSIG (0 bar)

Discharge Pressure: 0 PSIG (0 bar)

The maximum limits are:

Oil Pressure: 200 PSID (13.8 bar)

Suction Pressure: 200 PSIG (13.8 bar)

Discharge Pressure: 400 PSIG (27.6 bar)

% Motor Current

Motor currents for both System 1 and 2 are displayedwhen this push-button is pushed.

The minimum limits on the display is 0% FLA. Themaximum limit on the display is 115% FLA.

Operating HoursStart Counter

Accumulated running hours on each compressor is dis-played. The counters for an individual system count to atotal of 99999 hours before rollover. Accumulated starts

S Y S # 2 O I L = 6 3 P S I D

S P = 6 1 , D P = 1 3 3 P S I G

SYSTEM 2PRESSURES

% MOTORCURRENT

H R S 1 = 1 4 3 , 2 = 3 8 2

S T R 1 = 2 5 , 2 = 3 7

OPER. HOURSSTART COUNTER

T H E F O L L O W I N G

A R E P R O G R A M M E D

1 M T R 1 = 5 7 % F L A

1 M T R 2 = 6 5 % F L A

OPTIONS

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34 YORK INTERNATIONAL

FIG. 13 DIP SWITCH S1 AND EPROM LOCATION

TABLE 1 SWITCH POSITION AND DISPLAY

DISPLAY/ SWITCH OPEN MESSAGE SWITCH CLOSED MESSAGESWITCH

1

2

3

4

5

6

7

8A M B I E N T & D I S C H P R

F A N C O N T R O L

D I S C H A R G E P R E S S U R E

F A N C O N T R O L

M A N U A L

L E A D / L A G

A U T O M A T I C

L E A D / L A G

S T A N D A R D C O N D E N S E R

F A N C O N T R O L

S H A R E D C O N D E N S E R

F A N C O N T R O L

E N G L I S H U N I T S

R E A D O U T

M E T R I C U N I T S

R E A D O U T

R E T U R N W A T E R

C O N T R O L

L E A V I N G W A T E R

C O N T R O L

L O C A L C O N T R O L

M O D E

R E M O T E C O N T R O L

M O D E

S T A N D A R D

A M B I E N T

L O W A M B I E N T

C O N T R O L

C O M F O R T

C O O L I N G

B R I N E & P R O C E S S

D U T Y

26001A

LD01098

TOP VIEW

SIDE VIEWRTC

031-01652-001

EPROM

TOP SIDE

OPEN POSITION(LEFT SIDE OF SWITCH ISPUSHED DOWN)

CLOSED POSITION(RIGHT SIDE OF SWITCH ISPUSHED DOWN)

S1

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FORM 150.60-NM5

35YORK INTERNATIONAL

SWITCH 4OPEN:

Chiller control will be from return water temperature.

CLOSED:

Chiller control will be from leaving water temperature.

SWITCH 5OPEN:

Display messages will show units of measure in Englishunits (°F, PSI, etc.).

CLOSED:

Display messages will show units of measure in Metricunits (°C, kPa, etc.).

SWITCH 6OPEN:

This MUST be selected for chillers with 4 or morefans where each refrigerant system will have fansof its own.

CLOSED:

This MUST be selected for 2 fan chillers wherefans are shared by both refrigerant circuits.

SWITCH 1OPEN:

The chilled liquid temperature setpoint can only be pro-grammed from 40 - 70°F* (4.4 - 21.1°C).*

CLOSED:

The chilled liquid temperature setpoint can be pro-grammed from 15 - 70°F* (-9.4 - 21.1°C).*

SWITCH 2OPEN:

The low ambient cut-out is fixed at 25°F (-3.9°C).

CLOSED:

The low ambient cut-out is programmable from 0 - 50°F(-17.8 - 10°C). A low ambient kit MUST be installed if theswitch is placed in this position.

SWITCH 3OPEN:

This mode allows a Remote Control Center or an ISNpanel to only view chiller operating conditions. It will notallow changes to any chiller controls or setpoints.

CLOSED:

This mode should be selected in typical applications. Itwill allow a Remote Control Center or an ISN panel tonot only view chiller operating conditions, but will alsoallow the remote panel to change chiller controls andsetpoints.

C O M F O R T

C O O L I N G

R E T U R N W A T E R

C O N T R O L

B R I N E & C O O L I N G

D U T Y

L E A V I N G W A T E R

C O N T R O L

S T A N D A R D

A M B I E N T

E N G L I S H U N I T S

R E A D O U T

L O W A M B I E N T

C O N T R O L

M E T R I C U N I T S

R E A D O U T

L O C A L C O N T R O L

M O D E

S T A N D A R D C O N D E N S E R

F A N C O N T R O L

R E M O T E C O N T R O L

M O D E S H A R E D C O N D E N S E R

F A N C O N T R O L

* Positioning of this switch also affects the range of adjustments on the Suction Pressure Cut-out (page 44) and the Low Leaving Water Temp.

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SWITCH 8OPEN:

Fan control will be by outside ambient temp. This will bethe standard mode of fan control for normal operation. Inthis mode, maximum chiller efficiency will be achieved. Ifthe Low Ambient option is installed, the fan control willautomatically change to pressure control at temperaturesbelow 25°F (-3.9°C). See page 74 for fan control sequence.

CLOSED:

Fan control is by discharge pressure only. This mode offan control will increase discharge pressure. It should beused if nuisance low suction pressure faults are experi-enced. See page 74 for fan control sequence.

NOTE: Discharge pressure transducers must be in-stalled. These are optional (Discharge PressureRead-out Option) unless a Low Ambient Kit isinstalled.

SWITCH 7OPEN:

SYS 1 can be selected as the lag compressor by clos-ing a user supplied contact between Terminals 13 and19. See Page 69.

CLOSED:

In this mode, the micro determines which compressor isassigned to the lead and the lag. A new lead/lag assign-ment is made whenever both compressors shut down.The micro will then assign the lead to the compressorwith the shortest anti-recycle time.

M A N U A L

L E A D / L A G

A M B I E N T & D I S C H P R

F A N C O N T R O L

A U T O M A T I C

L E A D / L A G

D I S C H A R G E P R E S S U R E

F A N C O N T R O L

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SCHEDULE/HOLIDAY is keeping the chiller from run-ning.

Run Permissive is an indicator that an external cyclingcontact (i.e. flow switch) connected to terminals 13 and14 is open, or a system switch(es) on the Microproces-sor Board is in the OFF position. Whenever the contactis open or a switch is OFF, the NO RUN PERM will bedisplayed.

This message informs the operator that the chilled liquidtemperature is below the point (determined by thesetpoint and control range) that the micro will bring thelead system on, or that the micro has not loaded thesystem far enough into the loading sequence to be readyto bring the lag system ON. The lag system will displaythis message until the loading sequence is ready for thelag system to start (TEMPERATURE DEMAND in theOPER DATA displays must be 5 or above before cool-ing load is established for the lag system to run).

GENERAL

Pressing the STATUS key will enable the operator to de-termine current chiller operating status as a whole and asindividual systems. The messages displayed will includerunning status, cooling demand, fault status, external cy-cling device status, and anti-recycle timer status. The dis-play will be a single message relating to the highest prior-ity message as determined by the micro. Status mes-sages fall into the categories of General and Fault Statuswith each of the categories discussed below.

GENERAL STATUS MESSAGE

Each of the general status messages with a descriptionof its meaning will follow. In the case of messages whichapply to individual systems, SYS 1 and SYS 2 mes-sages will both be displayed and may be different. Xsin the sample displays indicate numerical values willappear in actual displays.

This message informs the operator that the UNIT switchon the Control Panel is in the OFF position which willnot allow the chiller to run.

The DAILY SCHEDULE SHUTDOWN message indicatesthat the schedule programmed into the CLOCK SET

STATUS KEY

STATUSKEY

U N I T S W I T C H I S I N

T H E O F F P O S I T I O N

D A I L Y S C H E D U L E

S H U T D O W N

S Y S # 1 N O R U N P E R M

S Y S # 2 N O R U N P E R M

S Y S # 1 N O C O O L L O A D

S Y S # 2 N O C O O L L O A D

S Y S # 1 C O M P R U N N I N G

S Y S # 2 C O M P R U N N I N G

02711TG

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The COMP RUNNING message indicates that the re-spective compressor is running due to demand.

The anti-recycle timer message shows the amount oftime left on the respective anti-recycle timer. This mes-sage is displayed when demand requires the respectivesystem to start but is being held off due to the timer.

The anti-coincident timer is a software feature that guardsagainst 2 compressors starting simultaneously. This as-sures instantaneous starting current does not becomeexcessively high due to simultaneous starts. The microlimits the time between compressor starts to 1 minuteregardless of demand of the anti-recycle timer being timedout. The time shown on the anti-coincident timer is thetime left on the timer before the respective system willstart. Demand must be present for the message to bedisplayed and will only appear when the anti-recycle timerhas timed out.

This display informs the operator that the micro is limit-ing the loading of the system, based on motor current.By programming the AVERAGE CURR UNLOAD point,the micro will limit the loading of the compressor when-ever motor current rises above the programmed value.

This feature reduces the chance of a system faulting onhigh motor current, motor protector due to motor over-heating, or high discharge pressure which causes highmotor current. The feature also assures that motor life isnot compromised. Typically, the AVERAGE CURR UN-LOAD is programmed for 100% to assure that the com-pressor is allowed to load to its rated FLA.

Discharge Pressure Limiting takes affect when dischargepressure nears the point at which the high pressure cut-out will shut the system down causing total loss of cool-ing. When this message appears, discharge pressurehas exceeded the user programmable threshold and themicro is unloading the affected system to prevent shut-

down on a manual high pressure cut-out. Reloading willtake place when discharge pressure has dropped 60 PSIG(413.9 kPa) below the threshold.

Optional discharge pressure transducers must be in-stalled for this feature to operate. This is accomplishedby adding the Discharge Pressure Readout option.

The PUMPING DOWN message indicates that the re-spective compressor is presently in the process of pump-ing the system down. The compressor will either be in arecycling pumpdown or in a pumpdown prior to shut-down when this message is displayed. The messagewill disappear when the compressor shuts off.

If the MANUAL OVERRIDE key is pressed, the STATUSdisplay will display the message shown above. This willindicate that the Daily Schedule is being ignored andthe chiller will start-up when water temperature allows,UNIT Switch permits, and SYSTEM Switches permit.

This is a priority message and cannot be overridden byanti-recycle messages, fault messages, etc. when inthe STATUS Display mode. Therefore, do not expect tosee any other STATUS messages when in the MANUALOVERRIDE mode. MANUAL OVERRIDE is to be usedonly in emergencies or for servicing.

FAULT STATUS MESSAGES

Fourteen possible fault messages may appear when theSTATUS key is pressed. Whenever a fault message ap-pears, the safety thresholds on the chiller have beenexceeded and the entire chiller or a single system willbe shut down and locked out. A detailed explanation ofthe shutdown thresholds and associated information re-lated to each fault is covered in the SYSTEM SAFETIESsection (Page 57).

Chiller shutdown faults will shut the entire chiller downand lock it out, while system shutdown faults will onlyshut down and lock out the affected system (compres-sor).

A list of the fault messages are shown on the next page:

S Y S # 1 A R T M R X X X S

S Y S # 2 A R T M R X X X S

S Y S # 1 A C T M R X X S

S Y S # 2 A C T M R X X S

S Y S # 1 C R N T L I M I T I N G

S Y S # 2 C R N T L I M I T I N G

S Y S # 1 P U M P I N G D O W N

S Y S # 2 P U M P I N G D O W N

M A N U A L

O V E R R I D E

S Y S # 1 D S C H L I M I T I N G

S Y S # 2 D S C H L I M I T I N G

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39YORK INTERNATIONAL

C H I L L E R F A U L T :

L O W A M B I E N T T E M P

S Y S # 1 M O T O R C U R R E N T

S Y S # 2 M O T O R C U R R E N T

C H I L L E R F A U L T :

L O W W A T E R T E M P

S Y S # 1 H I G H D S C H

S Y S # 2 H I G H D S C H

C H I L L E R F A U L T :

H I G H A M B I E N T T E M P

S Y S # 1 L O W O I L P R E S S

S Y S # 2 L O W O I L P R E S S

C H I L L E R F A U L T :

1 1 5 V A C U N D E R V O L T A G E

S Y S # 1 H I G H O I L T E M P

S Y S # 2 H I G H O I L T E M P

S Y S # 1 O I L T E M P I N H I B

S Y S # 2 O I L T E M P I N H I B

S Y S # 1 H I M T R C U R R E N T

S Y S # 2 H I M T R C U R R E N T

S Y S # 1 L O W S U C T I O N

S Y S # 2 L O W S U C T I O N

S Y S # 1 P U M P D O W N F A I L

S Y S # 2 P U M P D O W N F A I L

CHILLER FAULTS SYSTEM FAULTS

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The ENTER key is also used to scroll through availabledata after any one of the following keys is pressed:

PROGRAM

SET SCHEDULE/HOLIDAY

OPER DATA

HISTORY

Cancel Key

The CANCEL key allows the user to change errors in thedata being programmed into memory.

When the CANCEL key is pressed, any data which hasbeen keyed in, but not entered, will be erased. The origi-nal values will re-appear on the display and the cursorwill return to the first character to be programmed in thedisplay message.

AM/PM Key

The AM/PM key allows the user to change AM/PM whileprogramming the correct time in the SET TIME display.The same key allows changing the AM/PM schedulewhile programming daily chiller start and stop times inthe SET SCHEDULE/HOLIDAY display.

Advance Day Key

The ADVANCE DAY key advances the day when theSET TIME display is being programmed. The day is nor-mally advanced to correspond to the current day of theweek. The day will advance a day at a time, each timethe key is pressed.

GENERAL

The ENTRY key allows the user to change numericalvalues programmed in as chiller setpoints, cut-outs,clock, etc.

Numerical Keypad

The NUMERICAL keypad provides all keys needed toprogram numerical values as required.

The * Key is used to designate holidays when program-ming special start and stop times for designated holi-days in the SET SCHEDULE/HOLIDAY display.

The +/- key allows programming -°C setpoints and cut-outs in the metric display mode.

Enter Key

The ENTER key must be pushed after any change ismade to setpoints, cut-outs or the system clock. Press-ing this key tells the micro to accept the new values intomemory.

If this is not done, the new numbers entered will be lostand the original values will be returned.

ENTRY KEYS

1 2 3

4 5 6

7 8 9

* 0 +/-

ENTER

CANCEL

AM/PM

ADVANCEDAY

ENTRYKEYS

02711TG

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DISCHARGE CUT-OUT

The DISCHARGE CUT-OUT is a microprocessor backupfor the mechanical high pressure cut-out located in eachrefrigerant circuit. Typically chillers with air-cooled con-densers should have the cut-out set at 395 PSIG (2.7mPa). Chillers with water-cooled condensers normal re-quire the cut-out to be set at 275 PSIG (1.9 mPa).

NOTE: In some water cooled condenser installations,the possibility exists for the condenser waterpump or the cooling tower to not be in operationwhen the chiller starts. This causes the dis-charge pressure to rise so rapidly that eventhough the mechanical high pressure cut-out isshutting down the compressor, the flywheel ef-fect may cause the pressure to continue to risecausing the relief valve to open with a subse-quent refrigerant loss. By programming the cut-out at the typical manual cut-out at 275 PSIG(1.9 mPa), refrigerant loss due to system op-eration problems will be eliminated.

To program the DISCHARGE CUT-OUT, key in the de-sired value and press the ENTER key. The new value willbe entered into memory and the display will advance tothe next user programmable limit.

The micro will accept a range of programmable valuesbetween 200 - 399 PSIG (1.4 - 2.8 mPa) for this cut-out.For this cut-out to be functional, the Discharge PressureReadout Option must be installed.

GENERAL

Pushing the PROGRAM key allows the user to program11 system operating limits. These limits include cutoutpoints for safeties, anti-recycle timer duration, and thereaction time of the microprocessor to abrupt changesin the chilled water temperatures.

After the PROGRAM key is pressed, the micro will firstrespond by displaying the DISCHARGE CUT-OUT. Asthe 11 limits are displayed, they may be reprogrammedusing the 12 ENTRY keys. New values will be pro-grammed into memory when the ENTER key is pushed.The ENTER key must also be used to advance the dis-play the operator views the 10 system operating limits.Each time the key is pushed, the display will advance tothe next limit.

If the operator attempts to enter an unacceptable value,the micro will respond with a momentary message indi-cating the value selected has been ignored. This errormessage is shown:

The 11 programmable limit displays are shown anddescribed below along with the range of values whichthe microprocessor will accept for each limit. THESEVALUES MUST BE CHECKED AND PROPERLY PRO-GRAMMED WHEN COMMISSIONING THE CHILLER.FAILURE TO PROPERLY PROGRAM THESE VALUESMAY CAUSE DAMAGE TO THE CHILLER OR OPERA-TION PROBLEMS.

PROGRAM KEYPROGRAMMING USER PROGRAMMABLE SAFETIES AND LIMITS

PROGRAMKEY

O U T O F R A N G E

T R Y A G A I N !

D I S C H A R G E C U T O U T

= 3 9 5 P S I G

02711TG

PROGRAMKEY

02711TG

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NOTE: It is required to first key in a 0 when program-ming this cut-out (Example: 0395 PSIG).

More details on this safety are outlined in the SYSTEMSAFETIES section.

OUTSIDE AIR TMP LOW CUT-OUT

The OUTSIDE AIR TMP LOW CUT-OUT allows the userto select the chiller low ambient temperature cutout point.If the ambient falls below this point the chiller will shutdown. Restart can occur, if demand allows, when tem-perature rises above the cut-out. This only applies tooutdoor air-cooled chillers.

For normal ambient applications, the cut-out is set at25.0°F (-3.9°C) and is NOT programmable. However, someusers may set the cut-out higher to shut down the chillerand take advantage of other less costly cooling sources.In this case, S1 Dip Switch #2 on the Micro Logic Boardmust be in the CLOSED position for Low Ambient Controlto allow programming the cut-out above 25°F (-3.9°C).

Low ambient applications in ambients less than 25.0°F(-3.9°C) require a low ambient kit to be installed. Other-wise nuisance low pressure and low motor current tripswill result. If a low ambient kit is installed, the cut-outmay be lowered as needed below 25°F (-3.9°C). If opera-tion is occasionally needed below 0°F (-17.8°C) the cut-out should be set at 00.0°F (-17.8°C). This will allowoperation at any temperature since the micro is onlyable to recognize temperatures above 1°F (-17.2°C), re-gardless of the display.

NOTE: Operation below 0°F (-17.8°C) may cause othertypes of nuisance safety shutdowns, but occa-sional shutdowns can usually be tolerated sincethe need for sustained operation at these tem-peratures is unlikely and temperatures rarely sta-bilize for any length of time below 0°F (-17.8°C).

The micro will accept a range of programmable valuesbetween 00.0° - 50.0°F (-17.8 - 10°C) for this cut-out, ifS1 Dip Switch #2 on the Micro Logic Board is in theCLOSED position. In the OPEN position, a fixed 25°F(-3.9°C) cutout is recognized.

To program the OUTSIDE AlR TMP LOW CUT-OUT, keyin the desired value and press the ENTER key. The newvalue will be entered into memory and the display willadvance to the next user programmable limit.

OUTSIDE AIR TMP HIGH CUT-OUT

The OUTSIDE AIR TMP HIGH CUT-OUT is selectable toestablish the high ambient cut-out point. If the ambientrises above this point, the chiller will shut down. Restartcan occur when temperature drops below the cut-out.This only applies to outdoor air-cooled chillers.

This cut-out is normally set at 130.0°F (54.4°C) to allowoperation to the absolute maximum temperature capa-bility of the electro-mechanical components.

To program the OUTSIDE AIR TMP HIGH CUT-OUT, keyin the desired value and press the ENTER key. The newvalue will be entered into memory and the display willadvance to the next user programmable limit.

The micro will accept a range of programmable valuesbetween 100.0 - 130.0°F (37.8 - 54.4°C) for this cut-out.

DISCHARGE PRESSURE UNLOAD

The DISCHARGE PRESSURE UNLOAD point is a pro-grammable limit to keep the system from faulting on thehigh discharge pressure cut-out should a system prob-lem or chiller problem occur. A typical problem would beif the cooling tower would become dirty on a water-cooledsystem. Pressure would rise and eventually cause thechiller to fault causing total loss of cooling. By unloadingthe compressors at high discharge pressures, the chilleris allowed to continue to run automatically at reducedcapacity until the dirty cooling tower can be attended to.

When the unload point is reached, the micro will auto-matically totally unload the affected compressor. Typi-cal maximum programmed limits would be 375 PSIG(2.6 mPa) for air-cooled chillers with 395 or 405 PSIG(2.7 or 2.8 mPa) high pressure cut-outs and 255 PSIG(1.8 mPa) water-cooled chillers with 275 PSIG (1.9 mPa)cut-outs.

Reloading will occur when the discharge pressure dropsto 60 PSIG (413.7 kPa) below the programmed unloadpressure and will increment one stage at a time as dic-tated by the loading timers.

To program the DISCHARGE PRESSURE UNLOAD, keyin the desired value and press the ENTER key. The newvalue will be entered into memory and the display willadvance to the next user programmable limit.

The micro will accept a range of programmable valuesbetween 200 - 390 PSIG (1.4 - 2.7 mPa) for the unloadpoint.

NOTE: It is required to first key in a 0 when program-ming this cut-out (Example: 0375 PSIG).

O U T S I D E A I R T M P L O W

C U T O U T = 2 5 . 0 F

O U T S I D E A I R T M P H I G H

C U T O U T = 1 3 0 . 0 F

D I S C H A R G E P R E S S U R E

U N L O A D = 3 6 0 P S I G

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for programming this control will be discussed in theSELECTION OF RETURN OR LEAVING CHILLED LIQ-UID CONTROL Section (Page 48).

ANTI RECYCLE TIME

The ANTI RECYCLE TIME selection allows the user toselect the compressor anti-recycle time to best suit hisneeds. Motor heating is a result of inrush current whenthe motor is started. This heat must be dissipated be-fore another start takes place or motor damage may re-sult. The anti-recycle timer assures the motor has suffi-cient time to cool before it is again restarted.

An adjustable timer allows for the motor cooling required,but gives the user the ability to extend the timer to cutdown on cycling. In some applications fast compressorstart response is necessary, in others it is not. Theseneeds should be kept in mind and the timer should beadjusted for the longest period of time tolerable. Although300 seconds is adequate motor cooling time, longer pe-riods will allow even more heat dissipation, reduce cy-cling, and possibly increase motor life.

To program the ANTI RECYCLE TIME, key in the de-sired value and press the ENTER key. The new value willbe entered into memory and the display will advance tothe next user programmable limit.

The micro will accept a range of programmable valuesbetween 300 - 600 seconds for this operating control.

LEAVING WATER TEMP CUT-OUT

The LEAVING WATER TEMP CUT-OUT protects thechiller from an evaporator freeze-up should the chilledliquid temp drop below the freeze point. This situationcould occur under low flow conditions or if the micro panelSETPOINT values are improperly programmed. Anytimethe leaving chilled liquid temperature (water or glycol)drops to the cut-out point, the chiller will shut down.Restart will occur when temperature rises above the cut-out if the anti-recycle timers are satisfied.

For chilled water applications (comfort cooling, SW1OPEN), the cut-out is automatically set at 36.0°F (2.2°C).This covers applications where leaving water tempera-tures are not designed to go below 40.0°F (4.4°C). Ifchilled liquid (glycol) temperatures are required below40°F, the cut out should be programmed for 4°F (2.2°C)below the desired leaving chilled liquid temperature.

AVERAGE CURRENT UNLOAD

The purpose of AVERAGE CURRENT UNLOAD is to pro-vide adequate motor cooling and to prevent the motor fromfaulting on high motor current. The motor current unloadfeature only unloads a compressor by a single step. Thisprovides more cooling to the motor and at the same timestill attempts to pull the water temperature down.

Unloading will only occur when a compressor is runningwith at least one step of loading above a fully unloadedstate. This feature will under no circumstances shut acompressor off.

Whenever Motor Current Unloading is activated, the com-pressor will stay in the unloaded state for 5 minutes.After the 5 minute time period, the micro will look atmotor current once again. If motor is 25% below the pro-grammed Motor Current Unload point, the compressorwill be allowed to reload, if water temperature allows.

To program the Motor Current Unload, key in the desiredvalue and press the ENTER Key. The new value will beentered into memory and the display will advance to thenext user programmable limit.

The micro will accept a range of programmable valuesbetween 80 - 105% for the unload point. A setting of100% is recommended for the unload point.

NOTE: When programming values from 80 - 99%, it isfirst required to key in a 0. Example: 090%.

RATE CONTROL TEMP

The RATE CONTROL TEMP establishes a temperaturerange over which the micro may override normal systemloading timers and react to actual rate of change of re-turn and leaving water temperature. This temperaturerange is slightly above the setpoint with its band widthbeing programmable. This control works in conjunctionwith the RATE SENSITIVITY which is also programmable.

These controls allow the chiller to adapt to a full range ofapplications. Depending on how the controls are set upthe chiller can be adapted to provide maximum response,demand limiting/energy saving, or reduced loader andcompressor cycling. Typically this value should beprogrammed for 00.1°F (0.05°C). When programmingvalues like 00.1°F (0.05°C), it is first required to keyin 00. Example: 00.1°F (0.05°C). Additional details

R A T E C O N T R O L T E M P

= 0 8 . 0 F

A N T I R E C Y C L E T I M E

= 6 0 0 S E C S

L E A V I N G W A T E R T E M P

C U T O U T = 3 6 . 0 F

A V E R A G E C U R R E N T

U N L O A D = 1 0 0 % F L A

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To program the LEAVING WATER TEMP CUT-OUT theBRINE & PROCESS MODE (SW1 CLOSED) must beselected, key in the desired value and press the ENTERkey. The new value will be entered into memory and thedisplay will advance to the next programmable limit.

The micro will accept a range of programmable valuesbetween 08.0 - 36.0°F (4.4 - 20°C) for this cut-out.

SUCTION PRESSURE CUT-OUT

The SUCTION PRESSURE CUT-OUT protects the chillerfrom an evaporator freeze-up should the system attemptto run with a low refrigerant charge. Anytime the suctionpressure drops below the cut-out point, the system willshut down.

NOTE: There are some exceptions, where suction pres-sure is permitted to temporarily drop below thecut-out point. Details are outlined in the SYS-TEM SAFETIES section.

For chilled water applications, the cut-out should be setat 44 PSIG (303.3 kPa). If glycol or brine is utilized withleaving water temperature designs below 40°F (4.4°C),the cut-out should be adjusted according to concentra-tion. A rule-of-thumb cut-out design is to drop the cut-out 1 PSIG (6.9 kPa) below 44 PSIG (303.4 kPa) forevery degree of leaving glycol below 40°F (4.4°C). In otherwords, 30°F (-1.1°C) glycol requires a 34 PSIG (234.4kPa) suction pressure cut-out.

To program the SUCTION PRESSURE CUT-OUT, key inthe desired value and press the ENTER key. The newvalue will be entered into memory and the display willadvance the next programmable limit.

The micro will accept a range of programmable values be-tween 20 - 70 PSIG (137.9 - 482.6 kPa) for this cut-out. Inthe COMFORT COOLING MODE (SW1 OPEN), the cut-out is adjustable from 44 - 70 PSIG (303.4 - 482.6 kPa). Inthe BRINE & PROCESS MODE (SWI CLOSED), the cut-out is adjustable from 20 - 70 PSIG (137.9 - 482.6 kPa).

RATE SENSITIVITY

The RATE SENSITIVITY establishes the rate of changeof return or leaving water temperature where the microwill over-ride the normal 30 - 150 seconds per stage load-ing rate which is based on error between setpoint andactual temperature.

The RATE SENSITIVITY is active when the leaving chilledliquid temperature is in the RATE CONTROL TEMPRANGE. In this range, if water temperature is droppingfaster than the RATE SENSITIVITY setting, the micro willnot load any more stages because water temperature isdropping quickly. This provides demand limiting and re-duces loader/compressor cycling and overshoot. If quickresponse is needed, RATE SENSITIVITY can be pro-grammed accordingly. When temperatures are in the RATECONTROL TEMP RANGE, loading will occur in intervalsaccording to both rate of water temperature change anderror in water temperature versus setpoint. This will over-ride the typical 30 - 150 seconds per stage based on errorin setpoint versus actual water temperatures. If water tem-perature is dropping faster than the RATE SENSITIVITY,no further loading will result and in some cases, the chillerwill unload to slow temperature drop.

RATE SENSITIVITY is also active in the CONTROLRANGE in RETURN OR LEAVING WATER CONTROL.Further loading will not occur if water temperature is drop-ping too fast regardless of whether temperature calls forfurther loading.

Typically this value should be programmed for 5.0°F(2.7°C). Additional details of programming this controlwill be discussed in the SELECTION OF RETURN ORLEAVING CHILLED LIQUID CONTROL Section (Page48).

NUMBER OF LOAD STEPS

The number of steps of loading must be programmed toassure proper loading sequence and temperature con-trol. This is done at the factory, but should be checkedagainst the table below:

Standard unloading requires programming for 5 steps.Optional unloading is not available on YCAJ110 - 130chillers. Therefore, all YCAJ110 - 130 must be pro-grammed for 5 steps. These chillers are limited to 5 stepsdue to the 4-cylinder compressors which are equippedwith only a single unloading solenoid.

NOTE: Hot Gas Bypass (Loadminder) should not becounted as a load step for programming pur-poses.

Program the number of steps as required. To program 5steps, the 0 key (05) must be pressed first.

S U C T I O N P R E S S U R E

C U T O U T = 4 4 P S I G

R A T E S E N S I T I V I T Y

= 5 . 0 F / M I N .

N U M B E R O F L O A D S T E P S

= 1 0 ( E N T E R 5 7 O R 1 0 )

J110 J120 J130

STD. 5 STEPS 5 STEPS 5 STEPSOPT. NA NA NA

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GENERAL

The CLOCK is an internal system feature that allowsthe microprocessor to continuously monitor the time ofthe day. The micro will display actual time as well as theday of the week and the date when programmed. Thisfeature allows the microprocessor to provide an internalautomatic time clock feature for starting and stoppingthe chiller for each individual day of the week. Also pro-vided is a HOLIDAY feature which allows special start/stop programming for designated holidays.

The internal clock and schedule programming eliminatesthe need for an external time clock. Automatic chillerstart and stop will occur according to the programmedschedule.

If the user desires not to utilize the schedule feature, theSET SCHEDULE/HOLIDAY can be programmed to runthe chiller on demand as long as the UNIT and SYSswitches are ON.

Typical display messages will be shown which apply toeach key.

PROGRAMMING THE DAY, TIME AND THE DATE

Set Time

A message showing the day, time and date will be dis-played when the SET TIME key is pressed.

To program the day, time and date, first press the AD-VANCE DAY key until the appropriate day of the week isdisplayed. The day will advance each time the key ispressed.

The cursor will already be below the first digit of the time.Key in the new time, if required. Be sure to key in a 0before the other digits for times before 10 oclock., i.e.08:01.

After the time is keyed in, the cursor will advance to theAM/PM designation. To reprogram, press the AM/PMkey. When the key is pressed, the display will changeto the opposite time period. If no change is required,begin keying in the required date (the cursor will auto-matically skip to the first digit of the date [month] whena number key is pressed and the number will be placedin the first position).

NOTE: The AM/PM key can only be pressed once. Ifan error is made, press the CANCEL key andbegin again.

The date may be keyed in after AM/PM. The sequenceof the message display is month, day and year. Twodigits must be entered for each of these items. There-fore, a leading 0 may be required.

Once the desired information is keyed in, it may be storedin memory by pressing the ENTER key. After the EN-TER key is pressed, the cursor will move under the T ofTODAY.

The micro will accept any valid time or date. If an out ofrange value is entered, the micro will display the follow-

CLOCK KEYSPROGRAMMING THE SYSTEM CLOCK AND DAILY START/STOP SCHEDULE

CLOCKKEYS

SETTIME

T O D A Y I S S U N 1 1 : 1 2 A M

0 2 / 1 4 / 9 8

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ing message for 3 seconds before it reverts back to theSET TIME display message to let the user know thatanother try at reprogramming is necessary.

PROGRAMMING THE DAILY START/STOP ANDHOLIDAY SCHEDULE

Set Schedule/Holiday

Messages showing the start/stop schedule of each dayof the week as well as the holiday start/stop schedulecan be displayed after the SET SCHEDULE/HOLIDAYkey is pressed. The display can be scrolled through day-by-day simply by repetitively pressing the ENTER orADVANCE DAY key. A typical daily schedule display isshown below:

To reprogram any of the daily schedules, key in thenew START time. To change the AM/PM associatedwith the START time, press the AM/PM key. This willchange the AM/PM message to the opposite time pe-riod. The AM/PM key can only be pressed once. If anerror is made, press CANCEL and begin reprogram-ming again.

After the START time and the associated AM/PM havebeen programmed, the cursor will move to the STOPtime. Key in the STOP TIME and press the AM/PMkey if AM/PM requires changing.

When the ENTER key is pressed, the new START/STOPtime is entered and the display will scroll to the nextday. If an unacceptable time is entered, the followingmessage will be displayed.

For ease of programming, any values ENTERED forMONDAY will automatically be put in for the other daysof the week. Be aware of this anytime the MONDAYSCHEDULE is changed, since it changes times previ-ously programmed into other days. For scrolling throughthe days to view times programmed use the ADVANCEDAY KEY, not the ENTER KEY. This will assure thatafter viewing MONDAY, that the ENTER KEY is notpressed changing times programmed for the rest of theweek.

If the chiller is not cycled by the DAILY SCHEDULE, butis required to run whenever the system switches are on,all 00.00s should be programmed into the daily sched-

ule. This can be done manually for each day or by press-ing CANCEL and ENTER when the MONDAY START/STOP schedule appears.

NOTE: This will have no effect on the holiday schedule.

Continue to program each day as needed. After MONthrough SUN has been entered, the HOLIDAY messagewill be displayed.

The Holiday (HOL) START/STOP allows the user to des-ignate a specific day(s) for special requirements. This isprovided so that day(s) needing special start/stop re-quirements can be programmed without disturbing thenormal working schedule.

The start/stop times for the Holiday schedule are pro-grammed just as for any other day.

NOTE: Only one start/stop time can be programmedwhich will apply to each of the HOLIDAY daysselected.

After the ENTER key is pressed, a new message will bedisplayed to designate which days of the week are to beholidays.

In the above sample display, an * designates Tuesdayas a holiday.

When the display appears, the cursor will first stop be-hind Sunday. To designate a day as a holiday, press the* key. If a day is not to be a holiday, press the 0 key.Whenever the * or the 0 keys are pressed, the cursorwill advance to the next day. After all the holiday daysare programmed, press ENTER to store the new datainto memory. The display will then advance to the begin-ning of the Daily Schedule (MON).

The Holiday Schedule is only executed once by the mi-cro before it is erased from memory. This is done be-cause in most cases a special Holiday Schedule is onlynecessary once in a several month period. It also elimi-nates the need for operator intervention to erase theschedule after the holiday passes.

If an error is made while programming, press CANCEL.This will clear all programmed (*) holiday days. Theschedule can then be reprogrammed.

The 0 key will not cancel out a * and cannot be usedfor correcting a programming error.

SET SCHEDULE/HOLIDAY

O U T O F R A N G E

T R Y A G A I N !

M O N S T A R T = 0 6 : 0 0 A M

S T O P = 0 5 : 3 0 P M

O U T O F R A N G E

T R Y A G A I N !

H O L S T A R T = 0 8 : 3 0 A M

S T O P = 1 2 : 0 0 P M

S M T* W T F S

H O L I D A Y N O T E D B Y *

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programmed Daily Schedule is calling for the chiller tobe OFF (Daily Schedule Shutdown).

Once activated, MANUAL OVERRIDE is only active fora period of 30 minutes. It is for servicing only and isdesigned so that if left on accidentally, the microproces-sor will automatically return to the Daily Schedule.

MANUALOVERRIDE

M A N U A L

O V E R R I D E

Manual Override

When the MANUAL OVERRIDE key is pressed, the DailySchedule programmed into the chiller will be ignored andthe chiller will start-up when water temperature allows,unit switch permits, and system switches permit.

Normally this key is not used unless an emergency forcesthe chiller to require operation during a period where the

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the micro panel must be interrogated to determine whetherit is programmed for RETURN or LEAVING WATER CON-TROL. This can be accomplished by pressing the OP-TION key in the DISPLAY section of the keypad. Thisallows the user to determine the present mode of controlwithout gaining access to the Microprocessor Board andvisually checking the sometimes difficult to determineDip Switch position. When the OPTION key is pressed,a message THE FOLLOWING ARE PROGRAMMEDwill appear on the display for 3 seconds. The display willthen scroll through the 8 dip switch selections, eachappearing for 3 seconds. The 4th display will tell theuser whether leaving or return temperature is programmedon Switch 4. The 4th display message will read eitherRETURN WATER CONTROL or LEAVING WATERCONTROL and will appear for 3 seconds.

If a change is required, position Switch #4 on dip switchS1 on the Microprocessor Board (Fig. 13) as indicated:

RWT CONTROL: SW 4 OPEN(left side pushed down)

LWT CONTROL: SW 4 CLOSED(right side pushed down)

NOTE: In LWT CONTROL, water temperature may un-desirably rise when a compressor cycles off andcannot restart because the anti-recycle timer isstill timing out. The effects can be reduced byprogramming the anti-recycle timer (Page 43)for a minimum of 300 seconds if it isnt alreadyprogrammed for 300 seconds. If problems stillarise, switch to RWT CONTROL.

Once the dip switch #4 on the Microprocessor Board isproperly positioned, the user will be able to view the ap-propriate display when the CHILLED LIQUID TEMP/RANGE is pressed. This display will show one of thefollowing messages depending upon S1 positioning:

SELECTION OF RETURN OR LEAVING CHILLED LIQUID

R E T U R N W A T E R

T E M P C O N T R O L

L E A V I N G W A T E R

T E M P C O N T R O L

GENERAL

The user has the ability to select the type of chilled liq-uid temperature control by choosing either Return orLeaving Temperature Control. This provides the ability tofine tune the method of control for comfort cooling orbatch/process cooling loads.

In many cases, comfort cooling will be best controlledby RETURN WATER CONTROL. This will assure a mini-mum of cycling compressors/loaders with stable leavingchilled liquid temperatures as long as water flow GPM isheld constant and the Control Range (CR) is correctlyprogrammed.

LEAVING WATER CONTROL is also suitable for com-fort cooling, but may produce slightly more cycling de-pending upon the RATE SENSITIVITY programmed.Optional stages of loading are recommended to reducecycling. In most cases, Leaving Water Control will bemore precise unless compressor cycling is encountered.Anticipation and timers are built into the micro-processors control algorithms to eliminate compressorand loader cycling enabling LEAVING WATER CONTROLto be used in most applications. The control algorithmutilizes PID control.

For batch and process applications, LEAVING WATERCONTROL will allow for precise temperature control. Inthese applications chilled liquid temperature control ismore important than compressor/loader cycling. WhenLEAVING WATER CONTROL is utilized, it is recom-mended to have optional steps of loading on each com-pressor. This assures minimum tonnage per step whichreduces the possibility of compressor and loader cyclingthat is critical to precisely controlling temperature.

RETURN WATER CONTROL may also be used on batchand process application and should provide adequatecontrol. However, it will prove to be less responsive withslightly more leaving chilled liquid temperature variation.RETURN WATER CONTROL may become necessaryto use if too much compressor cycling is noted with cor-responding water temperature fluctuation when in Leav-ing Water Control.

After determining the mode of control best suited for theapplication (RETURN OR LEAVING WATER CONTROL),

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GENERAL

After Return or Leaving Chilled Liquid Control is selectedaccording to the users application and Switch #4 of DipSwitch S1 on the Micro Board is properly configured toselect Return or Leaving control, the chilled liquid set-points can then be programmed into the control panel.Switch #4 of S1 must be properly programmed or anincorrect display message will appear when the CHILLEDLIQUID TEMP/RANGE key is pressed. SEE SELEC-TION OF RETURN OR LEAVING CHILLED LIQUIDCONTROL Page 48 if needed.

If remote temperature setpoint is being utilized, the RE-MOTE RESET TEMP RANGE must be programmed.The following information will cover programming bothreturn and leaving control. Refer to either the RETURNor LEAVING WATER CONTROL section as required be-low. Programming the REMOTE RESET TEMP RANGEis discussed later in this manual on Page 72.

PROGRAMMING RETURN WATER CONTROL

Chilled LiquidTemp/Range

When the CHILLED LIQUID TEMP/RANGE key ispressed, the following message will be displayed for 3seconds indicating Dip Switch S1, Switch #4 on the Mi-croprocessor Board is programmed properly:

If this message is incorrect, see the SELECTION OFRETURN OR LEAVING CHILLED LIQUID CONTROLsection (Page 48) for instructions to reprogram the Mi-croprocessor Dip Switch S1, Switch #4.

The display will then scroll to a second message & hold:

This message will display the users Design LeavingWater Temperature (LWT) setpoint (44.0° F [6.7°C] inthe sample above). Even though return water tempera-ture control is being utilized, the object is to provide con-stant design leaving water temperature. It is the DesignLeaving Water Temperature setpoint (LWT) which mustbe programmed into the microprocessor.

Also included in this message is the CONTROL RANGE(CR). The CONTROL RANGE is the temperature rangewhich loading/unloading will take place. The lower limitof the CONTROL RANGE is always equal to the setpointand automatically appears when the setpoint is keyedin. The upper limit of the CR must be programmed.

In the above sample message, with a CR = 44.0 - 54.0°F(6.7 - 12.2°C), the chiller will be completely off at a re-turn water temperature of 44.0°F (6.7°C) and fully loadedat a return water temperature of 54.0°F (12.2°C). Partialloading will occur in equal temperature intervals between44° and 54°F (6.7 and 12.2°C). Unloading will occur asreturn temperature drops below 54°F (12.2°C) with thechiller cycling completely off at 44.0°F (6.7°C). These

SETPOINTS KEYSPROGRAMMING CHILLED LIQUID SETPOINTS AND REMOTE RESET TEMP RANGE

SETPOINTSKEYS

CHILLED LIQUIDTEMP / RANGE

R E T U R N W A T E R

T E M P C O N T R O L

L W T = 4 4 . 0 F

C R = 4 4 . 0 T O 5 4 . 0 F

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The micro will accept a range of programmable LWT val-ues from 10.0 - 70.0°F (-12.2 - 21.1°C) (See SWITCH1, Page 35). It will also accept a value for the upper limitof the CR of 4 - 20°F (2.2 - 11.1°C) above the LWTSetpoint.

If brine or glycol is used in the system, chilled liquidtemperatures below 40°F (4.4°C) may be desired. To pro-gram setpoints below 40°F (4.4°C), Dip Switch S1, Switch#1 on the Microprocessor Board must be properly pro-grammed. (See Page 34, Fig. 13). If the switch is incor-rect, when setpoints below 40°F (4.4°C) are entered aswell as when unacceptable values are entered, the fol-lowing message will be displayed.

Loading and unloading occurs in defined incrementsthroughout the Control Range according to the differencebetween return water temperature and the LWT setpoint.Loading is limited by a 60 second timer, while unloadingis not.

Loading may be inhibited or unloading may occur if themicro senses that the Rate Sensitivity is exceeded inthe Control Range or Rate Control Range to prevent over-shoot. This action will override incremental unloading.Further details regarding loading/unloading and RateControl will follow.

PROGRAMMINGRETURN WATER RATE CONTROL

Programmable RATE CONTROL is designed to limit com-pressor/loader cycling thus saving energy and reducingwear on mechanical components. It also reduces thepossibility of overshoot. RATE CONTROL will allow themicro to react to fast changes in water temperature be-yond normal responses dictated by the difference be-tween actual return water temperature and setpoint.

RATE CONTROL requires programming the temperaturerange (RATE CONTROL TEMP) above the CONTROLRANGE (CR) where rate control is desired. Additionally,the actual rate of change (RATE SENSITIVITY) of watertemperature which the micro uses as a control refer-ence must also be programmed.

Refer to Fig. 14 as you read the following text. A typicalleaving water temperature setpoint of 45°F (7.2°C) is usedwith a 45° - 55°F (7.2 - 12.8°C) CONTROL RANGE. ARATE CONTROL TEMP OF 65°F (18.3°C), which is typi-cal (10°F [5.5°C] above the high end the Control Range),is shown.

temperatures provide a Control Range differential of 54.0- 44.0 = 10.0°F (12.2 - 6.7 = 5.6°C).

Once the upper limit of the CR is programmed, the CON-TROL RANGE (CR) differential must always equal theactual water temperature drop (∆T) across the evapora-tor with the chiller completely loaded. Keep this in mindwhen programming the high end of the CR. In many cases,due to improper flows, actual temperature drop occursacross the evaporator (∆T) will not equal design. Forproper operation, adjust flow as needed or program theCONTROL RANGE as needed. However accomplished,the CONTROL RANGE differential must equal theevaporator temperature drop when fully loaded or leavingwater temperatures well above or well below the desiredsetpoint will result.

To program the Chilled Liquid Setpoints, press theCHILLED LIQUID TEMP/RANGE key. The display willfirst exhibit a message that RETURN WATER TEMPCONTROL is selected and 3 seconds later automati-cally scroll to the next display of LWT and CR. The cur-sor will stop at the first digit of LWT. Key in the DesignLeaving Water Temperature (LWT) that is required inthe system. See the following:

After the Design Leaving Water Temperature (LWT) iskeyed in, the lower limit of the CR (Control Range) in thedisplay message will automatically change to a valueidentical to the LWT. See below:

The cursor will advance to the final entry which is theupper limit of the CR (Control Range). This value mustbe programmed to equal the design LWT plus the CRdifferential (∆T across the evaporator fully loaded). In theabove examples it would be 44.0 + 10.0 = 54.0°F (6.7 +5.6 = 12.2°C):

Key in the upper limit of the CR and press ENTER. Oth-erwise the new values will not be entered into memory.After pressing the ENTER key, the display will continueto show the LWT and Control Range message until an-other key is pressed.

O U T O F R A N G E

T R Y A G A I N !

L W T = 4 4 . 0 F

C R = 4 4 . 0 T O 5 4 . 0 F

Design LeavingWater Temperature

L W T = 4 4 . 0 F

C R = 4 4 . 0 T O 5 4 . 0 F

The lower limit of the CRwill always automaticallyequal LWT.

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This may be required for small water loops. However, ifproblems arise where the chiller does not load and pulltemperature down, select 0.1°F (0.05°C).

To program the RATE CONTROL TEMP, first press thePROGRAM key. Repetitively press the ENTER key untilthe display below appears.

Key in the desired value and press the ENTER key. Thenew value will be entered into memory and the displaywill advance to the next user programmable limit.

The micro will accept a range of programmable valuesbetween 0.1 - 20°F (0.05 - 11.1°C).

NOTE: When programming values between 0.1 - 9.9°F(0.05 - 11.1°C), it is required to first key in a 0 or 00. Example: 05.9°F.

The next item which will require programming is the RATESENSITIVITY. The RATE SENSITIVITY is a means ofoverriding the loading/unloading timers when water tem-peratures are in the RATE CONTROL RANGE or theCONTROL RANGE. This allows the micro to react toabrupt downward changes in leaving or return water tem-peratures. The ability to respond to rate of change varia-tions in water temperatures gives the micro anticipa-tion capabilities to reduce the possibility of overshootin leaving water temperature.

In demand limiting applications, to avoid cycling or toavoid overshoot, RATE SENSITIVITY should be low. Thisallows the micro to go into rate control to prevent loadingwhenever water temperatures drop faster than the pro-grammed RATE SENSITIVITY. Rate Control can go intoeffect whenever water temperatures are in RATE CON-TROL RANGE or the CONTROL RANGE. For these ap-plications, a 3 - 5°F/min (1.7 - 2.8°C/min) RATE SENSI-TIVITY is recommended. This may be required for smallwater loops. However, if problems arise where the chillerdoes not load and pull temperature down, select 5°F/min (2.8°C/min).

NOTE: Too small of a RATE SENSITIVITY value se-lection may prevent loading due to varying flowsor if the water system allows a slug of cold waterto enter which falsely fools the micro into think-ing the RATE SENSITIVITY has been exceeded,preventing loading and allowing leaving watertemperature to rise above the desired tempera-ture. In some cases, unloading or compressorshutdown my result.

For normal comfort cooling, batch, or process applica-tions, select a high RATE SENSITIVITY of 5°F/min (2.8°C/min). Before RATE CONTROL can go into effect, thewater temperature would have to change at a very high

R A T E C O N T R O L T E M P

= 1 0 . 0 F

The RATE CONTROL TEMP establishes a temperaturerange (0.1 - 20°F [.05 - 11.1°C]) above the Upper Limitof CONTROL RANGE where the micro will limit loadingor cause unloading if the rate of change of water tem-perature reduction exceeds the programmed RATE SEN-SITIVITY. In Fig. 14 RATE CONTROL TEMP of 10°F(5.5°C) is used.

In the CONTROL RANGE and RATE CONTROL RANGE,loading/unloading will normally occur according to devia-tion from setpoint. Rate Control will function to preventloading if the water temperature change (leaving or re-turn) exceeds the RATE SENSITIVITY, even though de-viation from setpoint requires loading. This will reducethe chance of overshoot.

Above THE RATE CONTROL TEMP RANGE the microwill attempt to load the chiller every 60 seconds per stage.This allows the chiller to gain control of the water tem-perature as quickly as possible.

Since RWT Control utilizes the buffering of the waterloop and a wide control (loading/unloading) range, com-pressor/loader cycling is reduced, wear and tear on me-chanical parts is reduced, and pulldown demand is au-tomatically limited. This makes the selection of RATECONTROL TEMP and RATE SENSITIVITY values lesscritical unless short water loops are encountered.

Before programming the RATE CONTROL TEMP, the usershould first determine if typically the normal fastest al-lowable pulldowns are required or whether pulldown de-mand limiting is desired. Programmable values from 00.1- 20°F (0.05 - 11.1°C) are possible.

For normal pulldowns and quick response, a RATECONTROL TEMP of 0.1°F (0.05°C) is appropriate un-less excessive overshoot is noted.

For demand limiting, energy efficiency and minimumcycling, RATE CONTROL TEMPS of 10° - 20°F (5.6 -11.1°C) are advisable with temperatures around 20°F(11.1°C) most appropriate. This will cause the control toreact to water temperature rate of change well before thewater temperature drops into the CONTROL RANGE.

FIG. 14 RETURN WATER TEMPERATURECONTROL °F (°C)

65°(18.3°)

55°(12.8°)

45°(7.2°)

UPPER LIMIT OF RATECONTROL TEMP

RANGE

UPPER LIMIT OFCONTROL

RANGE (CR)

SETPOINT

ABOVE THE RATE CONTROLTEMP RANGE

hRATE CONTROL TEMP RANGE

(RATE CONTROL TEMP = 10°F [5.5°C])i

hCONTROL RANGE

(CR = 45 - 55°F [7.2 - 12.8°C])i

BELOW THE CONTROL RANGE

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will attempt to control to. The Target temperature is notprogrammable, but it is always the midpoint of the Con-trol Range (CR). Example: A control range of 44° - 46°F(6.7 - 7.8°C) will have a Target Temp of 45°F (7.2°C),which should equal the desired system leaving watertemperature. As mentioned before, the micro will be sat-isfied with a leaving temperature between 44° - 45°F (6.7- 7.2°C) unless the rate control is exceeded. Themicroprocessors rate control is designed to be less re-sponsive in the upper half of the Control Range (i.e. 45 -46°F [7.2 - 7.8°C]) than in the lower half (i.e. 44° - 45°F[6.7 - 7.2°C]). This is to prevent overshoot.

To program the Low-Limit Water Temperature (LWT) andthe Control Range (CR), press the CHILLED LIQUIDTEMP/RANGE key. This display will first exhibit a mes-sage that LEAVING WATER TEMP CONTROL is se-lected and 3 seconds later automatically scroll to thenext display of LWT and CR. The cursor will stop at thefirst digit of LWT. Key in the Low-Limit Water Tempera-ture (LWT) that is acceptable in the system. See below:

The micro will accept a range of programmable valuesfrom 10.0 - 70.0°F (-12.2 - 21.1°C) (See SWITCH 1,Page 35). If brine or glycol is used in the system, chilledliquid temperatures below 40°F (4.4°C) may be desired.

To program setpoints below 40°F (4.4°C), Dip Switch 1,Switch #1 on the Microprocessor Board must be prop-erly programmed. (See Page 35). If the switch is incor-rect, when setpoints below 40°F (4.4°C) are entered aswell as when unacceptable values are entered, the fol-lowing message will be displayed:

After the Low-Limit Water Temperature (LWT) is keyedin, the lower limit of the CR (Control Range) in the dis-play message will automatically change to a value iden-tical to the LWT. See below:

rate to exceed the RATE SENSITIVITY value pro-grammed. This will assure normal loading will occur. 5°F/min (2.8°C/min) also works well in comfort cooling appli-cations. If unsure of a RATE SENSITIVITY selection,use 5°F/min (2.8°C/min).

To program the RATE SENSITIVITY, first press the PRO-GRAM key. Repetitively press the ENTER key until thedisplay below appears.

Key in the desired value and press the ENTER key. Thenew value will be entered into memory and the displaywill advance to the next user programmable limit.

The micro will accept a range of programmable valuesbetween 0.5° - 5.0°F/min (0.3 - 2.8°C/min).

PROGRAMMING LEAVING WATER CONTROL

Chilled Liquid Temp/Range

When the CHILLED LIQUID TEMP/RANGE key ispressed, the following message will be displayed for 3seconds indicating Dip Switch S1, Switch #4 on the Mi-croprocessor Board is programmed properly:

If this message is incorrect, see the SELECTION OFRETURN OR LEAVING CHILLED LIQUID CONTROLSection (Page 50) for instructions to reprogram the Mi-croprocessor Dip Switch S1, Switch #4.

The display will then scroll to a second message and hold:

This message will display the Low-Limit Water Tempera-ture (LWT) and the Control Range (CR). In the sampleabove, the LWT is 44.0°F (6.7°C) and the CR is 44° -46°F (6.7 - 7.8°C).

The Control Range (CR) is the variation in leaving watertemperature which is acceptable in the system applica-tion. As long as leaving water temperature stays betweenthe low limit and midpoint of the Control Range (CR), theMicroprocessor will consider the temperature acceptableand will not initiate any loading/unloading reaction un-less Rate Control requires. The Low-Limit Water Tem-perature (LWT) is the minimum acceptable leaving watertemperature in the Control Range (CR), not the actualuser desired leaving water temperature setpoint.

The desired leaving water temperature is known as theTarget temperature which is the temperature the micro

R A T E S E N S I T I V I T Y

= 5 . 0 F / M I N .

L E A V I N G W A T E R

T E M P C O N T R O L

L W T = 4 4 . 0 F

C R = 4 4 . 0 T O 4 6 . 0 F O U T O F R A N G E

T R Y A G A I N !

L W T = 4 4 . 0 F

C R = 4 4 . 0 T O 4 6 . 0 F

Low-Limit Water Temperature (LWT)

L W T = 4 4 . 0 F

C R = 4 4 . 0 T O 4 6 . 0 F

The lower limit of the CRwill always automaticallyequal LWT.

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The cursor will advance to the final entry which is theupper limit of the CR (Control Range). This value is pro-grammed for the highest leaving water temperature whichis acceptable in the system application. Typically, 2°F(1.1°C) above the Low-Limit Water Temperature is ap-propriate. The micro will accept a value 1 - 5°F (0.5 -2.8°C) above the LWT for this value. 2°F (1.1°C) abovethe LWT is the default value.

Key in upper limit of the CR and press the ENTER key.Otherwise the new values will not be entered into memory.After pressing the ENTER key, the display will continueto show the LWT and Control Range message until an-other key is pressed.

CAUTION: Too small of a CR selection will cause com-pressor/loader cycling. If compressor cyclingoccurs, leaving water temperature may varyconsiderably as a result of a compressorthat cannot restart due to the anti-recycletimer. To eliminate this, increase the ∆T(temperature differential) of the CR and/orprogram the anti-recycle timer for a mini-mum of 300 seconds if it isnt already pro-grammed for 300 seconds.

NOTE: Whenever reprogramming the LWT and CR,keep in mind that the desired leaving water temp.or target should be midpoint of the CR.

Normal pulldown loading is limited by a 150 sec. loadingtimer between stages, with loading occurring wheneverleaving water temperature is in the upper half of the CON-TROL RANGE or above.

Below the Control Range, unloading will occur at 20 sec.intervals until temperatures fall back into the Control Zone.Unloading is controlled by a 20 sec. timer below theControl Zone.

The Rate Control software may prevent loading or causeunloading in the Rate Control Range or Control Range iftemperature drops faster than 2X the programmed RateSensitivity. This is to prevent overshoot.

In the lower half of the Control Range between the LowLimit and the Target, Rate Control will cause unloading iftemperature falls faster than 1X the programmed RateSensitivity. As before, this is to prevent overshoot.

Further details loading/unloading and Rate Control willfollow:

PROGRAMMING LEAVING WATER RATE CONTROL

Programmable RATE CONTROL is designed to limit com-pressor/loader cycling thus saving energy and reducing

wear on mechanical components. It also reduces thepossibility of overshoot. RATE CONTROL will allow themicro to react to fast changes in water temperature be-yond normal responses dictated by leaving water tem-perature and setpoint.

RATE CONTROL requires programming the temperaturerange (RATE CONTROL TEMP) above the CONTROLRANGE (CR) where rate control is desired. Additionally,the actual rate of change (RATE SENSITIVITY) of watertemperature which the micro uses as a control refer-ence must also be programmed.

Refer to Fig.15 as you read the following text. A typicallow limit water temperature of 44°F (6.7°C) is used witha 44 - 46°F (6.7 - 7.8°C) CONTROL RANGE (CR). ARATE CONTROL TEMP of 10°F (5.5°C), which is typical(10°F [5.5°C] above upper limit of the Control Range), isshown.

The RATE CONTROL TEMP establishes a temperaturerange (0.1 - 20°F [0.05 - 11.1°C]) above the Upper Limitof CONTROL RANGE where the micro will limit loadingif the rate of change of water temperature exceeds theRATE SENSITIVITY. In the above example a RATE CON-TROL TEMP of 10°F (5.5°C) is used. In the Rate ControlRange, the micro will prevent loading or may cause un-loading if the temperature drop exceeds 2X the RateSensitivity regardless of whether the 150 sec. loadingtimer and the deviation from setpoint is calling for load-ing.

At temperatures below the CONTROL RANGE, unload-ing will occur to bring temperatures back to within theCONTROL RANGE. The unloading timer will cause un-loading at 20 sec. intervals until temperatures fall backinto the CONTROL RANGE.

In the lower half of the Control Range between the LowLimit Water Setpoint (LWT) and the Target Tempera-ture (Desired Leaving Water Temperature), Rate Controlsoftware will cause unloading if temperature drops faster

UPPER LIMIT OF RATECONTROL TEMP RANGE

UPPER LIMIT OFCONTROL RANGE (CR)

TARGET

LOW LIMITOF CONTROLRANGE (LWT)

FIG. 15 LEAVING WATER TEMPERATURECONTROL °F (°C)

ABOVE THE RATE CONTROLTEMP RANGE

hRATE CONTROL TEMP RANGE

(RATE CONTROL TEMP = 10°F [5.5°C])i

hCONTROL RANGE

(CR = 44 - 46°F [6.7 - 7.8°C])i

BELOW THECONTROL RANGE

56°(13.3°)

46°(7.8°)

45°(7.2°)

44°(6.7°)

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NOTE: When programming values between 0.1 - 9.9°F,it is required to first key in a 0 or 00. Ex-ample: 05.9°F.

The next item which will require programming is the RATESENSITIVITY.

The RATE SENSITIVITY is a means of overriding theloading/unloading timers when water temperatures arein the RATE CONTROL RANGE or the CONTROLRANGE. This allows the micro to react to abrupt down-ward changes in leaving or return water temperatures.The ability to respond to rate of change variations inwater temperatures gives the micro anticipation capa-bilities to reduce the possibility of overshoot in leavingwater temperature.

In demand limiting applications, to avoid cycling, or toavoid overshoot, RATE SENSITIVITY should be low. Thisallows the micro to go into rate control to prevent loadingor cause unloading whenever water temperatures dropfaster than the programmed RATE SENSITIVITY. RateControl can go into effect whenever water temperaturesare in RATE CONTROL RANGE or the CONTROLRANGE. For these applications, a 3 - 5.0°F/min (1.7 -2.8°C/min). RATE SENSITIVITY is recommended. Thismay be needed for small water loops. However, if prob-lems arise where the chiller does not load or abruptlyturns a compressor off and fails to pull temperature down,select 5.0°F/min (2.8°C/min).

NOTE: Too small of a RATE SENSITIVITY Selectionmay prevent loading due to varying flows or if thewater system allows a slug of cold water to enterwhich falsely fools the micro into thinking theRATE SENSITIVITY has been exceeded, pre-venting loading and allowing leaving water tem-perature to rise above the desired temperature.

For normal comfort cooling, batch, or process applica-tions, select a high RATE SENSITIVITY of 5.0°F/min(2.8°C/min). Before Rate Control can go into effect, thewater temperature would have to change at a very highrate to exceed the RATE SENSITIVITY value pro-grammed. This will assure normal loading will occur atthe fastest possible speed. In most applications, 5.0°F/min (2.8°C/min). is suggested. If unsure of a RATESENSITIVITY selection, use 5.0°F/min (2.8°C/min).

To program the RATE SENSITIVITY, first press the PRO-GRAM key. Repetitively press the ENTER key until thedisplay below appears.

Key in the desired value and press the ENTER key. Thenew value will be entered into memory and the displaywill advance to the next user programmable limit.

than 1X the Rate Sensitivity. Otherwise, no other loadingor unloading will result in this temperature range.

In the upper half of the Control Range between the TAR-GET and the High Limit of the Control Range and in theRate Control Range, loading will take place in 150 sec.intervals until temperature drops below the TARGET tem-perature. The Rate Control software may prevent loadingor initiate unloading if temperature drops faster than 2Xthe programmed Rate Sensitivity.

Above the RATE CONTROL TEMP RANGE, the microwill attempt to load the chiller as fast as it can (150seconds per stage). This allows the chiller to gain con-trol of the water temperature as quickly as possible whilestill avoiding overshoot and limiting pulldown demand astemperature drops and rate control is implemented.

Since LWT Control does not have the water loop for buff-ering after a load/unload response and utilizes a narrowcontrol (loading/unloading) range, compressor/loadercycling can be a problem. This makes the selection ofRATE CONTROL TEMP and RATE SENSITIVITY valuesvery critical.

Before programming the RATE CONTROL TEMP, the usershould first determine if typically the fastest allowablepulldowns are required or whether pulldown demand lim-iting is desired. Programmable values from 0.1 - 20° F(0.05 - 11.1°C) are possible.

For normal pulldowns and quick response, a RATECONTROL TEMP of 0.1°F (0.05°C) is appropriate un-less excessive overshoot is noted.

For demand limiting, energy efficiency, elimination ofovershoot, and minimum cycling, RATE CONTROLTEMPS of 10 - 20°F (5.6 - 11.1°C) are advisable. Thiswill cause the controls to react to water temperature rateof change well before the water temperature drops intothe CONTROL RANGE. This may be required for smallwater loops. However, if problems arise where the chillerdoes not load and pull temperature down, select 0.1°F(0.05°C).

To program the RATE CONTROL TEMP, first press thePROGRAM key. Repetitively press the ENTER key untilthe display below appears.

Key in the desired value and press the ENTER key. Thenew value will be entered into memory and the displaywill advance to the next user programmable limit.

The micro will accept a range of programmable valuesbetween 0.1 - 20°F (0.05 - 11.1°C).

R A T E C O N T R O L T E M P

= 1 0 . 0 F

R A T E S E N S I T I V I T Y

= 5 . 0 F / M I N .

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The micro will accept a range of programmable valuesbetween 0.5 - 5.0°F/min (0.3 - 2.8°C).

LOADING AND UNLOADINGRETURN WATER TEMPERATURE CONTROL

In return water temperature control, loading and unload-ing will take place according to the difference betweenthe leaving water temperature setpoint and the actualreturn water temperature. By programming the CONTROLRANGE equal to the actual temperature drop across theevaporator fully loaded, the microprocessor will be ableto maintain the desired leaving water temperature bycontrolling off of the return water temperature (RWT).Simply, the micro will know that the chiller should befully loaded when the RWT is equal to the SETPOINT +CONTROL RANGE. As the RWT drops, the micro willunload the chiller which reduces the capacity (tempera-ture drop across the evaporator). This maintains the leav-ing water temperature at the desired setpoint.

Normal loading will occur at intervals of 60 seconds,according to temperatures determined by the formulabelow. Loading may be prevented due to the rate controlcircuitry. Anytime the return water temperature falls withinthe CONTROL RANGE or the RATE CONTROL RANGE,RATE CONTROL is in effect and loading may be pre-vented, if water temperature changes faster than the ratesensitivity. Loading will never occur in intervals fasterthan 60 sec. under any circumstances. This preventscycling of the compressors and loaders.

Unloading occurs on temperature drop at temperaturesdetermined by the formula below. Internal timers have noeffect on unloading.

The micro is capable of providing 5, 7, or 10 steps ofloading/unloading. The chiller MUST be programmed forthe number of steps which were ordered. Otherwise,improper operation and water temperature control prob-lems will result. YCAJ110 - 130 chillers MUST alwaysbe programmed for 5 steps since optional unloading isnot available.

The temperature between stages of loading/unloading isequal to the CONTROL RANGE divided by the numberof stages. For example:

CONTROL RANGE= 10°F (5.5°C)

Number of Stages = 5

10°F ) 5 = 2°F (5.5°C ) 5 = 1.1°C) between stages

In this example, the micro will add a stage of loadingeach time the return water temperature rises 2°F(1.1°C) assuming loading timers and rate control soft-ware allows.

The micro will unload a stage 2°F (1.1°C) below thetemperature at which it was loaded assuming unload-ing timers and rate control software allows.

Listed in Fig. 16 are the loading and unloading sequencesfor 5 steps of control. A typical setpoint of 45°F (7.2°C)with a cooling range of 10°F (5.5°C) is shown for ex-ample purposes. The chiller will be completely loaded ata return water temperature of 55°F (12.8°C) and will becompletely off at a temperature of 45°F (7.2°C), thusmaintaining a leaving water temperature of 45°F (7.2°C).As mentioned before, loading/unloading timers as wellas rate control software must be satisfied before load-ing/unloading will occur. This reduces the possibility ofcycling.

LOADING AND UNLOADINGLEAVING WATER TEMPERATURE CONTROL

In leaving water temperature control, loading and unload-ing will take place as needed to keep water temperaturein the CONTROL RANGE between the TARGET and LOWLIMIT WATER TEMPERATURE. As mentioned earlier inthis manual, the CONTROL RANGE is the temperaturerange of leaving water temperature that is acceptable tothe user and has been previously programmed into

FIG. 16 5 STEP LOADING/UNLOADING (RETURNWATER CONTROL) °F (°C)

LD02664

NOTE:

The micro controls loading and unloadingon a 10 STEP scale regardless of the num-ber of stages present. Therefore, loadingand unloading responses on 5 Step (stan-dard) chillers may appear delayed (timebetween stages increased) when miss-ing steps are activated or deactivated bythe micro.

5 STEP (STANDARD)

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memory using the CHILLED LIQUID TEMP RANGE KEY.Usually this is a window of water temperatures of about2 - 3°F (1.1 - 1.7°C). The micro will cause loading andunloading actions to occur as needed to keep leavingwater temperatures in the lower half of this range. Referto Fig. 17 to aid in understanding the loading and un-loading scheme performed by the microprocessor.

FIG. 18 LEAVING WATER CONTROL LOADING/UNLOADING

5 STEP (STANDARD)TEMPERATURE

RISE LOAD UNLOAD5 LEAD COMP + 1 STEP, LAG COMP + 1 STEP 4 LEAD COMP + 1 STEP, LAG COMP UNLOADED LEAD COMP + 1 STEP, LAG COMP UNLOADED3 LEAD COMP UNLOADED, LAG COMP UNLOADED LEAD COMP UNLOADED, LAG COMP UNLOADED2 LEAD COMP + 1 STEP, LAG COMP OFF LEAD COMP + 1 STEP, LAG COMP OFF1 LEAD COMP UNLOADED, LAG COMP OFF LEAD COMP UNLOADED, LAG COMP OFF

LEAD COMP OFF, LAG COMP OFF LEAD COMP OFF, LAG COMP OFFTEMPERATURE

FALL

FIG. 17 LEAVING WATER TEMPERATURE CONTROL

UPPER LIMIT OFCONTROL RANGE

TARGET

LOW LIMIT WATERTEMPERATURE

ABOVE THE RATE CONTROL RANGE

RATE CONTROL TEMP RANGE

CONTROL RANGE (CR)

BELOW THE CONTROL RANGE

Within the lower half of the CONTROL RANGE, the mi-croprocessor may call for further unloading if the RateSensitivity is exceeded. If temperature drop exceeds 1Xthe Rate Sensitivity, the micro will unload the chiller toprevent overshoot.

Normal unloading will occur if leaving water temperatureshould fall into the temperature range BELOW THECONTROL RANGE which is below the programmed LowLimit WATER TEMPERATURE. The microprocessor willunload the chiller in 20 sec. intervals until water tem-perature rises back into the CONTROL RANGE.

If leaving water temperature rises into the upper half ofCONTROL RANGE or above, the microprocessor will loadthe chiIler as needed in 150 sec. intervals until tempera-tures fall into the lower half of the CONTROL RANGE. Ifthe rate of drop in water temperature exceeds 2X theprogrammed Rate Sensitivity, no further loading or un-loading will result since the micro sees the temperaturedropping at an excessive rate anticipating temperaturewill soon fall into the CONTROL RANGE.

The micro is capable of providing 5, 7, or 10 steps ofloading/unloading. The chiller MUST be programmed forthe number of steps which were ordered. Otherwise,improper operation and water temperature control prob-lems will result. YCAJ110 - 130 chillers MUST alwaysbe programmed for 5 steps since optional unloading isnot available.

NOTE. The micro controls loading and unloading re-sponses on a 10 step scale regardless of thenumber of stages present. Therefore, loadingand unloading responses on 5 step chillers mayappear delayed (time between steps increased)when missing steps are activated or de-activatedby the micro, 5 STEP CONTROL IS STAN-DARD.

Fig. 18 shows the loading and unloading sequences for5 steps of control.

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Monitoring motor current assures that motor life is notcompromised due to low motor current. Low motor cur-rent may be caused by loss or low voltage on the highvoltage supply which could quickly result in motor fail-ure. Low motor current may also result from low refriger-ant charge. This assures that the compressor does notrun with a low suction pressure condition while the lowpressure bypass is de-activated.

The micro begins monitoring for low motor current after 4seconds after a compressor starts. If after 4 secondsthe motor current drops below 15% FLA, the micro willshut the compressor down.

NOTE: Do not confuse FLA and RLA. FLA (full-loadamps) is approximately 1.2 x RLA. RLA (run-ning load amps) specified on the motor name-plate is typical current demand under rated op-erating conditions in a fully loaded system. There-fore, do not expect to see 100% FLA when thesystem is fully loaded. In this condition, cur-rents may run approximately 65 - 85% FLA.

Three internal temperature sensors are built into the motorstator. These sensors are wired into the motor protectormodule located inside the Motor terminal box. As themotor windings heat and cool, the resistance of the mo-tor temperature sensors will change. If the windings over-heat, the change in resistance in the sensors will besensed by the Motor protector module. The module willopen its MP contacts breaking the 115VAC fed to themotor contactor. When the motor contactor de-energizes,motor current falls to zero. The low motor current is sensedby the microprocessor and the system is shut down.

Once tripped, the Motor Protector Module will not resetunless power (115VAC) is removed for at least 5 sec-onds from the control panel. Therefore, after 2 more startattempts, the micro will lock out on a low motor currentsafety and requires 115VAC control power to be removedand reapplied along with manual reset via the systemswitch.

A mechanical high pressure cut-out is located on eachcompressor discharge or in the compressor head. Thisis the primary high pressure safety in the system. Anymicroprocessor controls are secondary.

Anytime discharge pressure exceeds 405 PSIG (2.8mPa), the contacts in the high pressure cut-out will openwhich removes 115VAC from the motor protector mod-ule. When 115VAC control power is lost to the module,the modules MP contacts open breaking the 115VACfed to the motor contactor. The motor contactor de-ener-gizes and motor current falls to zero. The low motor cur-rent is sensed by the microprocessor and the system isshut down. For more information see the MOTOR CUR-RENT SAFETY section (Page 59).

There are three types of System Safeties: The ManualReset type, the Automatic Reset type, and AnticipationSafety Controls. These safeties protect the chiller fromdamage anytime a safety threshold is exceeded by ei-ther shutting the system(s) down or by altering systemloading. Continuous monitoring by the microprocessorassures that instantaneous reactions result. A statusdisplay message will indicate when a system(s) or theentire chiller is shut down due to a fault or when Antici-pation safeties are operating.

An explanation of these safeties will follow.

MANUAL RESET SAFETIES (3 Faults and Lockout)

A Manual Reset Safety will shut the affected systemdown whenever the safety threshold is exceeded. Auto-matic restart will occur after the first 2 shutdowns whenthe anti-recycle timer times out, if temperature demandexists. After any combination of 3 Manual Reset Safe-ties in a 90-minute time period, the affected system willshut down and lock out on a FAULT.

After a system has shut down 3 times and locked out, afault display indicating the last system fault will appearon the STATUS display message. This is accessible bypressing the STATUS key.

To reset a locked out system, turn the affected systemswitch on the Microprocessor Board (Page 69) to theOFF position.

CAUTION: Before returning a locked out system toservice, a thorough investigation of the causeof the fault should be made. Failure to re-pair the cause of the fault while manuallyallowing repetitive restarts may cause fur-ther expensive damage to the system.

Each of the Manual Reset Safeties will be discussed indetail below.

MOTOR CURRENT(Low Motor Current, Motor Protector, andMechanical High Pressure Cutout Safety)

This safety combines several safeties into one. The mi-cro monitors for low motor current as sensed by the C.T.,the mechanical motor protector, and the high pressurecutout.

An example of the fault display is shown below:

SYSTEM SAFETIES

S Y S # 1 M O T O R C U R R E N T

S Y S # 2 M O T O R C U R R E N T

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The Discharge Pressure Safety Cut-out is programmableby the user (Page 41). An example of a discharge pres-sure fault display message is shown below.

NOTE: This safety is only operable if optional dischargepressure transducers are installed.

Oil Pressure Safety

The Oil Pressure Safety assures that the compressorsmechanical components receive proper lubrication. Themicro begins monitoring compressor oil pressure after 4seconds of operation. For operating periods of 4 sec-onds to 30 seconds, oil pressure must be greater than 5PSID. From 30 seconds to 240 seconds, oil pressuremust be greater than 20 PSID. After 240 seconds, oilpressure must be greater than 25 PSID for as long asthe compressor continues to run. If the required oil pres-sure limits are not met, the system will shut down.

The micro computes differential oil pressure by mea-suring oil pump pressure and subtracting suction pres-sure (Oil - Suction = Oil PSID).

An example of an oil pressure fault display message isshown below.

Pumpdown Safety

The Pumpdown Safety assures that a compressor doesnot run unless it completes a proper pumpdown. Thisprevents operation of a refrigerant system which has aleaking liquid line solenoid valve.

On shutdown, the system must pump down to the suc-tion pressure cut-out within 300 seconds or the systemwill shut down. If the system performs 3 unsuccessfulpumpdowns in a row, the system will fault & lock out.

An example of the Pumpdown Fault display message isshown below.

High Oil Temp Safety

This safety protects the compressor from catastrophicfailure by sensing when an internal problem occurs that

S Y S # 1 H I G H D S C H

S Y S # 2 H I G H D S C H

S Y S # 1 L O W O I L P R E S S

S Y S # 2 L O W O I L P R E S S

S Y S # 1 P U M P D O W N F A I L

S Y S # 2 P U M P D O W N F A I L

Auto-restart will be permitted after a shutdown when dis-charge pressure drops to below 330 PSIG (2.3 mPa)which allows the mechanical high pressure cut-out toreset and its contacts to close. This re-applies 115VACto the motor protector closing the MP contact. A faultlock-out will result if safety thresholds are exceeded threetimes in a 90-minute period.

Suction Pressure Safety

The Suction Pressure Safety assures that the system isnot run under low refrigerant conditions or due to a prob-lem which will not allow proper refrigerant flow.

For the first 30 seconds of operation, the low suctionpressure bypass is in operation. After 30 seconds ofoperation, the micro begins monitoring suction pressureand continues to do so as long as the compressor runs.For operation periods of 30 seconds to 240 seconds,suction pressure must be greater than 50% of the Suc-tion Pressure Cut-out. After 240 seconds, suction pres-sure must be greater than the cut-out.

NOTE: A transient timer is built into software to assurethat short term fluctuations in suction pressuredue to fan cycling, loading, etc. do not causenuisance trips on low suction pressure.

After the system has pumped down and suctionpressure reaches cut-out plus 5 PSIG, the tran-sient timer is readied for action. If suction pres-sure drops below the cut-out point, the 120 sec-ond transient timer begins timing. As long assuction pressure doesnt drop below 50% of cut-out during the 120 second period and rises abovecut-out before the timer times out, the systemwill continue to run.

The Suction Pressure Safety Cut-out is programmableby the user (Page 44). An example of a suction pres-sure fault message is shown below.

Discharge Pressure Safety

The Discharge Pressure Safety assures that the sys-tem pressure does not exceed safe working limits whichcould open a relief valve or other pressure relief devicecausing refrigerant loss.

This safety is a back-up for the mechanical safety in thesystem. Anytime the cut-out point is exceeded, the sys-tem will shut down.

S Y S # 1 L O W S U C T I O N

S Y S # 2 L O W S U C T I O N

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NOTE: Do not confuse FLA and RLA. FLA (full loadamps) is approximately 1.2 x RLA. RLA (run-ning load amps) specified on the motor name-plate, is typical current demand under rated op-erating conditions in a fully loaded system. There-fore, do not expect to see 100% FLA when thesystem is fully loaded In this condition, currentsmay run approximately 65 - 85% FLA.

INDIVIDUAL START INHIBIT SAFETIES

An Individual System Start Inhibit Safety will shut therespective system down on a fault when the safety thresh-old is exceeded and allows automatic restart after thecondition causing the shutdown clears. Restart will oc-cur only after anti-recycle timers are satisfied and de-mand requires.

When the chiller is shut down on one of these safeties,a message will appear on the STATUS display informingthe operator of the problem. This is accessible by press-ing the STATUS key.

Low Oil Temperature Inhibit Safety

Low oil temperature assures the compressor is not al-lowed to start until the oil is free of liquid refrigerant. Thisis accomplished by assuring that the oil temperature isa minimum of 15°F (8.3°C) above ambient temperature.

In effect, this safety assures that the compressor oilheater is operating and that it has been on long enoughafter power application for all refrigerant to have beenexpelled from the oil.

NOTE: This safety will only be operational if the chilleris equipped with an I/O Expansion Board.

An example of the High Oil Temp safety display is shownbelow.

AUTOMATIC RESET SAFETIES

An Automatic Reset Safety will shut the entire chillerdown on a fault when the safety threshold is exceededand allows automatic restart after the condition causingthe shutdown clears. Restart will occur only after anti-recycle timers are satisfied and demand requires.

A reset hysteresis is built in so repetitive faulting andclearing will not occur in a short time period. An ex-ample would be if ambient temperature dropped belowthe cut-out, temperature would have to rise 5°F (2.8°C)above the cut-out before the fault lockout would clearand restart can occur.

causes high internal compressor temperatures. It alsoprotects the compressor from overheating, due to im-proper cooling from hot suction gas, high water tempera-tures, or high discharge pressures.

The compressor will shut down whenever the sump tem-perature exceeds 180°F (82.2°C) for the first minute ofoperation or 160°F (71.1°C) after one minute of opera-tion.

An example of the Oil Temp Inhibit safety display isshown below:

MANUAL RESET SAFETIES (1 Fault and Lockout)

A Manual Reset Safety will shut the affected systemdown and lock it out whenever the safety threshold isexceeded.

After a system has shut down and locked out, a faultdisplay indicating the last system fault will appear onthe STATUS display message. This is accessible bypressing the STATUS key.

To reset a locked out system, turn the affected systemswitch on the Microprocessor Board (Page 69) to theOFF position.

CAUTION: Before returning a locked out system toservice, a thorough investigation of the causeof the fault should be made. Failure to re-pair the cause of the fault while manuallyallowing repetitive restarts may cause fur-ther expensive damage to the system.

Each of the Manual Reset Safeties will be discussed indetail below.

High Motor Current Safety

The High Motor Current Safety assures that motor life isnot diminished due to operating beyond the current rat-ing of the motor. The Micro begins monitoring motor cur-rent after 3 seconds of operation. If motor current ex-ceeds 120% FLA after 3 seconds of operation, the com-pressor will shut down. After 4 seconds of operation,motor current must be less than 115% FLA as long asthe compressor continues to run.

An example of the High Motor Current display is shownbelow:

S Y S # 1 H I G H O I L T E M P

S Y S # 2 H I G H O I L T E M P

S Y S # 1 H I G H M T R C U R R

S Y S # 2 H I G H M T R C U R R

S Y S # 1 O I L T E M P I N H I B

S Y S # 2 O I L T E M P I N H I B

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Under Voltage Safety

The Under Voltage Safety assures that the system isnot operated at voltages where malfunction of the micro-processor could result in system damage. Whenever themicroprocessor senses an onboard power supply fail-ure, the chiller is shut down. Restart will occur whenpower is restored. The microprocessor circuitry is ca-pable of operating at voltages 10% below the nominal115VAC supply to the panel.

An example of the Under Voltage Safety display mes-sage is shown below:

Flow Switch

The microprocessor monitors the closure of the flowswitch to assure that water flow is present in the evapo-rator which prevents freeze-ups. The flow switch drycontacts are connected between terminals 13 & 14 ofthe TB3 terminal block (Fig. 12). If the flow switch opens,the chiller will shut down and the following status mes-sage will be displayed.

Closure of the flow switch, when flow is present, will causethe message to disappear and auto-restart will occur.

CAUTION: NEVER BYPASS A FLOW SWITCH. THISWILL CAUSE DAMAGE TO THE CHILLERAND VOID ANY WARRANTIES.

Power Failure Safety

Whenever power is removed or lost and then reapplied,auto-restart will occur after a 2 minute anti-recycle timerelapses. This is the same anti-recycle timer which isprogrammable from 5-10 minutes; however, it automati-cally is set to 2 minutes after a power failure.

This safety assures that the motor has a minimum of 2minutes to cool under any circumstances allowing muchof the internal heating due to starting to be dissipatedbefore another start occurs.

ANTICIPATION SAFETY CONTROLS

Anticipation controls are built into the software to pre-vent safety shutdowns by automatically overriding tem-perature controls if system pressures near safety thresh-olds. This allows the chiller to continue to run under re-duced capacity to avoid total loss of cooling resultingfrom a lockout on a safety.

When the chiller is shut down on one of these safeties,a message will appear on the STATUS display informingthe operator of the problem. This is accessible by press-ing the STATUS key.

Details concerning each of the three Automatic ResetSafeties follow.

Low Water Temperature Safety

The Low Water Temperature Safety assures that theevaporator is not damaged from freezing due to improp-erly set control points. Whenever the chilled liquid tem-perature drops below the programmable cut-out, thechiller will shut down. Restart will not occur until tem-perature rises 5°F (2.8°C) above the cut-out point, loaddemand requires, and anti-recycle timers allow.

The Low Water Temperature Safety Cut-out is program-mable by the user (Page 43). An example of the LowWater Temperature Fault display message is shownbelow:

Low Ambient Temperature Safety

The Low Ambient Temperature Safety assures that thechiller does not run in low ambients where potential dam-age could result due to low system pressures.

The Low Ambient Cut-out is programmable by the user(Page 44). An example of the Low Ambient TemperatureFault display message is shown below:

High Ambient Temperature Safety

The High Ambient Temperature Safety assures that thechiller does not run in ambients above 130°F (54.4°C)where potential malfunction of system mechanical andelectrical components may result. Whenever the out-door ambient exceeds 130°F (54.4°C) (non-programmable)the chiller will shut down. Restart will not occur untiltemperature drops to 2°F (1.1°C) below the cut-out point,load demand requires, and anti-recycle timers allow.

The High Ambient Cut-out is programmable (Page 44)for chiller cut-out at temperatures below 130°F (100° -130°F) [54.4°C (37.8°C - 54.4°C)]. An example of theHigh Ambient Temperature Fault display message isshown below:

C H I L L E R F A U L T :

L O W W A T E R T E M P

C H I L L E R F A U L T :

L O W A M B I E N T T E M P

C H I L L E R F A U L T :

H I G H A M B I E N T T E M P

C H I L L E R F A U L T :

1 1 5 V A C U N D E R V O L T A G E

S Y S # 1 N O R U N P E R M

S Y S # 2 N O R U N P E R M

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Anticipation safeties monitor suction and discharge pres-sure and unload the compressors as needed. The microwill display a message on the STATUS DISPLAY when-ever these controls are in operation.

CURRENT LIMITING

If current exceeds the value programmed by the user(Page 45), the micro will unload the affected compressor.

Whenever Current Limiting is activated, the compressorwill stay in the unloaded state for 5 minutes. After the 5minute time period, the micro will look at motor currentonce again. If motor is 25% below the programmed Mo-tor Current Unload point, the compressor will be allowedto reload, if water temperature allows.

This safety assures that the motor will receive propercooling from the refrigerant which promotes longer motorlife.

An example of the message displayed when current lim-iting is in effect is shown below:

Discharge Pressure Unloading

If the discharge pressure exceeds the value programmedby the user (Page 42), the micro will unload the affectedcompressor. Automatic reloading will occur when pres-sure drops 60 PSI (413.7 kPa) below the programmedvalue. This feature reduces the chance of faulting on thehigh discharge pressure cut-out.

On water cooled chillers, this safety reduces the chanceof tripping the relief valve due to a very high rate of rise inpressure resulting from a controls problem which wouldcause condenser water flow to be interrupted. In thiscase, the pressure rise is so fast, refrigerant loss mayoccur through the relief valve even though the high pres-sure cut-out has opened and the compressor is in themidst of stopping.

An example of the message displayed when dischargepressure unloadings in effect is shown below:

INTERNAL TIMERS AND PUMPDOWN CONTROLS

ANTI-RECYCLE TIMER

Anytime a compressor shuts down for any reason, re-start cannot occur until the programmable Anti-recycleTimer (Page 43) has timed out (timer starts with the com-

pressor start). Even though the Anti-recycle timer hastimed out, a minimum of 2 minutes (2-minute start-uptimer) must always elapse after a compressor stop be-fore it may again restart.

If a power failure occurs, the anti-recycle timers will re-set to 2 minutes after power is re-applied.

If the anti-recycle timer is preventing a start, the timerposition in seconds may be viewed by pressing the STA-TUS key. A sample display is shown below.

ANTI-COINCIDENCE TIMER

The Anti-Coincidence Timer assures that 2 compressorscan never start simultaneously. This assures that ex-cessive current demand will never result. A one minutetime delay will always separate compressor starts.

The Anti-Coincidence Timer can be viewed, when it isactive, by pressing the STATUS key. A sample displayis shown below.

PUMPDOWN CONTROLS

Pumpdown control will pump down a system to the suc-tion pressure cut-out whenever the compressor shutsdown on a normal shutdown. Additionally, a recyclingpumpdown is employed on an as needed basis to as-sure that liquid does not accumulate in the evaporatoron an OFF system, while cold chilled liquid is flowing,through the evaporator. Since pumpdown at start-up isnot employed, the liquid line solenoid valve will openimmediately when a compressor starts.

Pumpdown on shutdown will pump a system downwhenever a system shuts down, except in two circum-stances. A pumpdown will not occur whenever a faultcauses a shutdown or when UNIT rocker switch isturned off. Pumpdown will continue until the suction pres-sure falls below the suction pressure cut-out. If the pres-sure never drops below the cut-out, pumpdown will con-tinue until a 3-minute pumpdown timer has expired.

During pumpdown, the following STATUS message willbe displayed:

The PUMPING DOWN message indicates that the re-spective compressor is presently in the process of pump-ing the system down. The compressor will either be in a

S Y S # 1 D S C H L I M I T I N G

S Y S # 2 D S C H L I M I T I N G

S Y S # 1 A R T M R 1 0 2 S

S Y S # 2 A R T M R 1 0 2 S

S Y S # 1 C O M P R U N N I N G

S Y S # 1 A C T M R 5 6 S

S Y S # 1 C U R R L I M I T I N G

S Y S # 2 C U R R L I M I T I N G

S Y S # 1 P U M P I N G D O W N

S Y S # 2 P U M P I N G D O W N

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62 YORK INTERNATIONAL

recycling pumpdown or in a pumpdown prior to shut-down when this message is displayed. The messagewill disappear when the compressor shuts off.

Recycling pumpdown is initiated while a compressoris off, able to run, and is in a No Cooling Load state. Itcan be initiated 45 minutes after either of the followingtwo conditions are met:

1. Sat Suction Temp > LCHWT - 1.5°F (0.8°C)and

Ambient Temp > LCHWT - 6°F (3.3°C)

2. The compressor has been idle for 2 hours and Suc-tion Pressure is greater than the cut-out.

The 45-minute timer assures that excessive pumpdownsdo not occur.

After 120 pumpdowns, uninterrupted by a cooling start,the system will cease to pump down. Pumpdowns willbegin again after a cooling start occurs. This is to pre-vent oil loss in the system. However, if one systemreaches 120 pumpdowns while the other system is run-ning for cooling, the running (lead) compressor will beshut off if the off (lag) compressor is available for start.At this point, the lead compressor will pump down andshut off while the lag compressor starts and assumesthe lead. The previous running compressor will now have120 pumpdowns available.

S Y S # 1 P U M P D O W N F A I L

S Y S # 2 P U M P D O W N F A I L

A pumpdown failure fault will occur if a system performs3 unsuccessful pumpdowns in a row. Unsuccessfulassumes that the system was not able to pump down tothe suction pressure cut-out in 3 minutes. The systemwill require a manual reset to restart. The following is anexample of this safety message.

NOTE: Under some circumstances, a pumpdown mayoccur when a compressor is called to come onfor cooling. If this occurs, the compressor willrestart to provide cooling after the pumpdown iscomplete and the anti-recycle timer times out.

Recycling pumpdown will increase the number of startslogged in the micropanel; however, it will have no effectupon the life of the compressors.

Pumpdown Safety

The Pumpdown Safety assures that a compressor doesnot run unless it completes a proper pumpdown. Thisprevents operation of a refrigerant system which has aleaking liquid line solenoid valve.

On shutdown, the system must pump down to the suc-tion pressure cut-out within 300 seconds or the systemwill shut down. If the system performs 3 unsuccessfulpumpdowns in a row, the system will fault and lock out.

An example of the Pump down fault display message isshown below.

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GENERAL

The PRINT keys allow the operator to obtain a remoteprintout of real-time system operating data and a print-out of system data at the instant of the fault on the lastthree faults which occurred on the chiller.

If a remote printer is not being used, or the desire is toobtain data locally at the panel, the same keys allowaccess to identical fault data. Identical and additionalreal-time information is available by using a combinationof the PRINT keys and the other keys on the keypad.

An explanation of the use of the keys for remote printeror local data retrieval will follow. An optional printer (Page87) will be required for remote printout.

REMOTE PRINTOUT

Oper Data

The OPER DATA key allows the operator to remotelyobtain a printout of current system operating parameters.When the key is pressed, a snapshot will be taken ofsystem operating conditions and panel programmingselections. This data will be temporarily stored in memoryand transmission of this data will begin to the remoteprinter. As the data is transmitted, it will be erased frommemory.

A sample printout is shown in Fig. 19.

PRINT KEYS

FIG. 19 OPERATING DATA PRINTOUT

YORK INTERNATIONAL CORPORATIONRECIPROCATING WATER CHILLERS

SYSTEM STATUS8:45AM 4/17/98

SYS 1 COMPRESSOR RUNNINGSYS 2 ANTI-COIN TIMER 13 SEC.

RETURN WATER TEMP 65.0 DEGFLEAVING WATER TEMP 54.0 DEGFLOW WATER CUTOUT 36.0 DEGFSETPOINT TEMP 45.0 DEGFOUTSIDE AIR TEMP 75.0 DEGFLOW AMBIENT CUTOUT 10.0 DEGFLOW PRESSURE CUTOUT 4 4 PSIGLEAD SYSTEM SYS 1CONTROL TYPE LCHWTCOOLING RANGE 45.0 TO 47.0 DEGF

SYSTEM 1 DATA

COMPRESSOR STATUS ONMOTOR AMPS 5 0 %FLASUCTION PRESSURE 6 1 PSIGDISCHARGE PRESSURE 143 PSIGOIL PRESSURE 7 5 PSIDLIQUID LINE SOLENOID OFFRUN PERMISSIVE ONSTAGES OF LOADING 1FORWARD FANS OFFREVERSE FANS OFFHOT GAS BYPASS VALVE OFF

SYSTEM 2 DATA

COMPRESSOR STATUS ONMOTOR AMPS 0 %FLASUCTION PRESSURE 6 1 PSIGDISCHARGE PRESSURE 8 0 PSIGOIL PRESSURE 1 PSIDLIQUID LINE SOLENOID OFFRUN PERMISSIVE ONSTAGES OF LOADING 1FORWARD FANS 1REVERSE FANS OFFHOT GAS BYPASS VALVE OFF

S M T W T F S *=HOLIDAYSUN START=06:00AM STOP=11:00AMMON START=06:00AM STOP=11:00AMTUE START=06:00AM STOP=11:00AMWED START=06:00AM STOP=11:00AMTHU START=06:00AM STOP=11:00AMFRI START=06:00AM STOP=11:00AMSAT START=06:00AM STOP=11:00AMHOL START=00:00AM STOP=11:00AM

PRINTKEYS

OPERDATA

02711TG

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64 YORK INTERNATIONAL

FIG. 20 HISTORY PRINTOUT

NOTE: In actual print-outs, this would be one continuous print-out.

YORK INTERNATIONAL CORPORATIONRECIPROCATING WATER CHILLERS

SAFETY SHUTDOWN NUMBER 1SHUTDOWN @ 8:48AM 4/17/98

SYS 1 STATUS: NO FAULTSSYS 2 MOTOR CURRENT SHUTDOWN

RETURN WATER TEMP 65.0 DEGFLEAVING WATER TEMP 54.0 DEGFLOW WATER CUTOUT 36.0 DEGFSETPOINT TEMP 45.0 DEGFOUTSIDE AIR TEMP 75.0 DEGFLOW AMBIENT CUTOUT 10.0 DEGFLOW PRESSURE CUTOUT 44 PSIGLEAD SYSTEM SYS 1CONTROL TYPE LCHWTCOOLING RANGE 45.0 TO 47.0 DEGF

SYSTEM 1 DATA

COMPRESSOR STATUS ONMOTOR AMPS 50 %FLASUCTION PRESSURE 61 PSIGDISCHARGE PRESSURE 143 PSIGOIL PRESSURE 75 PSIDLIQUID LINE SOLENOID OFFRUN PERMISSIVE ONSTAGES OF LOADING 1FORWARD FANS 2REVERSE FANS OFFHOT GAS BYPASS VALVE OFF

SYSTEM 2 DATA

COMPRESSOR STATUS ONMOTOR AMPS 0 %FLASUCTION PRESSURE 61 PSIGDISCHARGE PRESSURE 80 PSIGOIL PRESSURE 1 PSIDLIQUID LINE SOLENOID OFFRUN PERMISSIVE ONSTAGES OF LOADING 1FORWARD FANS 1REVERSE FANS OFFHOT GAS BYPASS VALVE OFF

YORK INTERNATIONAL CORPORATIONRECIPROCATING WATER CHILLERS

SAFETY SHUTDOWN NUMBER 2SHUTDOWN @ 8:47AM 4/17/98

SYS 1 STATUS: NO FAULTSSYS 2 MOTOR CURRENT SHUTDOWN

RETURN WATER TEMP 65.0 DEGFLEAVING WATER TEMP 54.0 DEGFLOW WATER CUTOUT 36.0 DEGFSETPOINT TEMP 45.0 DEGFOUTSIDE AIR TEMP 75.0 DEGFLOW AMBIENT CUTOUT 10.0 DEGFLOW PRESSURE CUTOUT 44 PSIGLEAD SYSTEM SYS 1CONTROL TYPE LCHWTCOOLING RANGE 45.0 TO 47.0 DEGF

SYSTEM 1 DATA

COMPRESSOR STATUS ONMOTOR AMPS 50 %FLASUCTION PRESSURE 61 PSIGDISCHARGE PRESSURE 143 PSIGOIL PRESSURE 75 PSIDLIQUID LINE SOLENOID ONRUN PERMISSIVE ONSTAGES OF LOADING 1FORWARD FANS 2REVERSE FANS OFFHOT GAS BYPASS VALVE OFF

SYSTEM 2 DATA

COMPRESSOR STATUS ONMOTOR AMPS 0 %FLASUCTION PRESSURE 61 PSIGDISCHARGE PRESSURE 80 PSIGOIL PRESSURE 1 PSIDLIQUID LINE SOLENOID OFFRUN PERMISSIVE ONSTAGES OF LOADING 1FORWARD FANS 1REVERSE FANS OFFHOT GAS BYPASS VALVE OFF

YORK INTERNATIONAL CORPORATIONRECIPROCATING WATER CHILLERS

SAFETY SHUTDOWN NUMBER 3SHUTDOWN @ 8:47AM 4/17/98

SYS 1 STATUS: NO FAULTSSYS 2 MOTOR CURRENT SHUTDOWN

RETURN WATER TEMP 65.0 DEGFLEAVING WATER TEMP 54.0 DEGFLOW WATER CUTOUT 36.0 DEGFSETPOINT TEMP 45.0 DEGFOUTSIDE AIR TEMP 75.0 DEGFLOW AMBIENT CUTOUT 10.0 DEGFLOW PRESSURE CUTOUT 44 PSIGLEAD SYSTEM SYS 1CONTROL TYPE LCHWTCOOLING RANGE 45.0 TO 47.0 DEGF

SYSTEM 1 DATA

COMPRESSOR STATUS ONMOTOR AMPS 50 %FLASUCTION PRESSURE 61 PSIGDISCHARGE PRESSURE 143 PSIGOIL PRESSURE 75 PSIDLIQUID LINE SOLENOID ONRUN PERMISSIVE ONSTAGES OF LOADING 1FORWARD FANS 2REVERSE FANS OFFHOT GAS BYPASS VALVE OFF

SYSTEM 2 DATA

COMPRESSOR STATUS ONMOTOR AMPS 0 %FLASUCTION PRESSURE 61 PSIGDISCHARGE PRESSURE 80 PSIGOIL PRESSURE 1 PSIDLIQUID LINE SOLENOID OFFRUN PERMISSIVE ONSTAGES OF LOADING 1FORWARD FANS 1REVERSE FANS OFFHOT GAS BYPASS VALVE OFF

History

The HISTORY key allows the operator to remotely ob-tain a printout of information relating to the last 3 SafetyShutdowns which occurred. The information is stored atthe instant of the fault regardless of whether the faultcaused a lockout to occur. The information is also notaffected by power failures (long term internal memorybattery backup is built into the circuit board) or manualresetting of a fault lockout.

When the HISTORY key is pressed, a Printout is trans-mitted of all system Operating conditions which werestored at the instant the fault occurred for each of the 3SAFETY SHUTDOWN BUFFERS. There is one buffer

HISTORY(storage area) for data related to each of the last 3 safetyshutdowns.

The printout will begin with the most recent fault whichoccurred. The most recent fault will always be stored asSAFETY SHUTDOWN NO. 1 (See printout Fig. 20). Iden-tically formatted fault information will then be printed forSAFETY SHUTDOWN NO. 2 and SAFETY SHUTDOWNNO. 3.

Information contained in the SAFETY SHUTDOWN Buff-ers is very important when attempting to troubleshoot asystem problem. This data reflects the system condi-tions at the instant the fault occurred and often revealsother system conditions which actually caused the safetythreshold to be exceeded. (See Fig. 20)

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FORM 150.60-NM5

65YORK INTERNATIONAL

LOCAL DISPLAY READOUTOper Data

The OPER DATA key also allows the user to scroll throughadditional real time display information about the chillersystem which is not available from the DISPLAY keys.This information covers a wide range of data which in-cludes fan status, loading status, liquid line solenoidstatus, run time, etc. A total of 20 different displays areoffered.

When the OPER DATA key is pressed, the followingmessage will appear:

Repetitively pressing the ENTER key allows the opera-tor to scroll through the 20 available displays.

In the information that follows, a sample message alongwith an explanation of its meaning is provided for all 20messages.

This message provides a real time display of the timeleft on the Load Timer. The Load Timer is a constantlyrecycling timer that the micro utilizes in conjunction withrate control and temperature deviation from setpointto determine when loading should occur. The timer willalways start at 150 sec.; however, it may count to 0 ata rate of up to 5 secs. per actual second of time.

This message provides a real timer display of the timeleft on the Unload Timer. The Unload Timer is a con-stantly recycling timer that the micro utilizes in conjunc-tion with rate control and temperature deviation fromsetpoint to determine when unloading should occur. Thetimer will always start at 150 sec.; however, it may countto 0 at a rate of up to 5 secs. per actual second of time.

This message informs the operator what stage of load-ing the chiller system is presently on as a result of com-mands from the microprocessor. This is a coded numberand the steps must be decoded to be meaningful. Thedecoding varies according to the number of stages pro-grammed (Page 44). Tables for decoding the display mes-sage are shown at the top of the next column:

P R E S S E N T E R T O

D I S P L A Y D A T A

L O A D T I M E R

1 4 0 S E C S

U N L O A D T I M E R

1 2 2 S E C S

T E M P E R A T U R E D E M A N D

5 STAGESTEP

0: Both Compressors OFF

*1: Lead Compr Unloaded, Lag Compr OFF*2: Lead Compr Unloaded, Lag Compr OFF

*3: Lead Compr Loaded, Lag Compr OFF*4: Lead Compr Loaded, Lag Compr OFF

*5: Lead Compr Unloaded, Lag Compr Unloaded*6: Lead Compr Unloaded, Lag Compr Unloaded

*7: Lead Compr Loaded, Lag Compr Unloaded*8: Lead Compr Loaded, Lag Compr Unloaded

*9: Lead Compr Loaded, Lag Compr Loaded*10: Lead Compr Loaded, Lag Compr Loaded

* On some STEPS, actual Loading will NOT change.

This message provides a real time display of the aver-age rate of change of leaving chilled water as seen bythe micro. A (-) or (+) sign is also shown to indicate atemperature fall or a temperature rise.

This message informs the operator which system is inthe lead.

This message informs the operator that the micro hascommanded the auxiliary contacts (optional) for thechilled water pump to close.

This message informs the operator that the micro sensesthe outdoor ambient temperature is below 40°F (4.4°C)and is commanding the Evaporator Heater to turn on.Once turned on, the heater will turn off at 45°F (7.2°C).

This message informs the operator that the micro hascommanded the auxiliary contacts (optional) for the con-denser water pump to close.

T E M P E R A T U R E R A T E

1 . 5 D E G F / M I N

L E A D S Y S T E M I S

S Y S T E M N U M B E R 1

E V A P O R A T O R W A T E R

P U M P S T A T U S O N

E V A P O R A T O R H E A T E R

S T A T U S O F F

C O N D E N S E R W A T E R

P U M P S T A T U S O F F

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This message informs the operator whether the revers-ing fan is active on SYS 2.

This message informs the operator whether the Hot GasSolenoid is ON or OFF. The Micro will activate the HotGas signal regardless of whether or not this option isinstalled.

The Run Time for SYS 2 since the last start is displayed.

History

The HISTORY key also allows the user to scroll throughthe SAFETY SHUTDOWN buffers to display informationrelating to the last 3 Safety Shutdowns which occurred.Information contained in the SAFETY SHUTDOWN Buff-ers is very important when attempting to troubleshoot asystem problem. This data reflects system conditionsat the instant the fault occurred.

Information is stored in the SAFETY SHUTDOWN Buff-ers on every fault regardless of whether the fault causeda Lockout to occur. The information is also not affectedby power failures (long term internal memory batterybackup is built into the circuit board) or manual resettingof a fault lockout.

When the HISTORY key is passed, the following mes-sage will appear.

The operator must then select which SAFETY SHUT-DOWN Buffer which is desired. When deciding this, keepin mind that Buffer No. 1 is always the most recent fault.As new fault information is stored, it is always placed inBuffer No. 1, No. 1 is loaded to No. 2, No. 2 is loaded toNo. 3, and information previously in No. 3 is discarded.

To select a buffer, simply press the 1, 2, or 3 EN-TRY key and press ENTER. Repetitively pressing theENTER key will allow the operator to scroll through theinformation available in the SAFETY SHUTDOWN Buffer.

In the information that follows, a sample message alongwith an explanation is provided for all available messages.

S Y S 2 H O T G A S B Y P A S S

V A L V E S T A T U S O N

S Y S 2 R U N T I M E

0 S E C S

D I S P L A Y S A F E T Y S H U T -

D O W N N O . 1 ( 1 T O 3 )

OFF: SYS 1 Liquid Line Solenoid De-energized(Closed).

ON: SYS 1 Liquid Line Solenoid Energized (Open).

This message informs the operator of the number ofstages of loading which are active on SYS 1.

This message informs the operator of the number of for-ward running fans which are active on SYS 1.

This message informs the operator whether the revers-ing fan is active on SYS 1.

This message informs the operator whether the Hot GasSolenoid is ON or OFF. The micro will activate the HotGas signal regardless of whether or not this option isinstalled.

The Run Time for SYS 1 since the last start is displayed.

OFF: Sys 2 Liquid Line Solenoid De-energized(Closed).

ON: Sys 2 Liquid Line Solenoid Energized (Open).

This message informs the operator of the number ofstages of loading which are active on SYS 2.

This message informs the operator of the number of for-ward running fans which are active on SYS 2.

S Y S 2 S T A G E S O F

L O A D I N G 1

S Y S 2 F O R W A R D F A N S

S T A T U S O F F

S Y S 2 R E V E R S E F A N

S T A T U S O F F

S Y S 1 L I Q U I D L I N E

S O L E N O I D S T A T U S O F F

S Y S 1 S T A G E S O F

L O A D I N G 2

S Y S 1 F O R W A R D F A N S

S T A T U S O N

S Y S 1 R E V E R S E F A N

S T A T U S O F F

S Y S 1 H O T G A S B Y P A S S

V A L V E S T A T U S O F F

S Y S 1 R U N T I M E

2 0 0 S E C S

S Y S 2 L I Q U I D L I N E

S O L E N O I D S T A T U S O F F

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67YORK INTERNATIONAL

This message indicates the type of chilled water controlselected at the time of the fault. LCHWT = Leaving Wa-ter Control. ECHWT = Entering or Return Water Control.

This display shows the Cooling Range (CONTROLRANGE, CR) which was selected at the time of the fault.

This message indicated the entering condenser watertemperature at the time of the fault. A fixed value will bedisplayed if the optional sensor is not installed.

This message indicates the leaving condenser water tem-perature at the time of the fault. A fixed value will bedisplayed if the optional sensor is not installed.

This message indicates whether Compressor 1 was ONor OFF at the time of the fault.

This message indicates SYS 1 motor current at the timeof the fault.

This display shows the suction pressure of SYS 1 at thetime of the fault.

This message indicates SYS 1 discharge pressure atthe time of the fault.

This display shows the oil pressure of SYS 1 at the timeof the fault.

This message informs the operator of the time and dateof the fault.

This message informs the operator of the nature of thefault which occurred.

This message indicates the Return Water Temperatureat the time of the fault.

This message indicates the Leaving Water Temperatureat the time of the fault.

This display shows the Low Water Cutout (Leaving) whichwas programmed at the time of the fault.

This display shows the Setpoint Temp which was pro-grammed at the time of the fault.

This message indicates the Outdoor Ambient Tempera-ture at the time of the fault.

This display shows the Low Ambient Cutout programmedat the time of the fault.

This display shows the Low Pressure Cutout programmedat the time of the fault.

This message indicates which system was in the leadat the time of the fault.

S H U T D O W N O C C U R R E D

3 : 2 4 P M 6 / 3 / 9 8

S Y S # 1 L O W O I L P R E S S

S Y S # 2 N O F A U L T S

R E T U R N W A T E R T E M P

5 2 . 7 D E G F

L E A V I N G W A T E R T E M P

4 4 . 3 D E G F

L O W W A T E R C U T O U T

3 6 . 0 D E G F

S E T P O I N T T E M P

4 4 . 0 D E G F

O U T S I D E A I R T E M P

7 7 . 6 D E G F

L O W A M B I E N T C U T O U T

3 5 . 0 D E G F

L O W P R E S S U R E C U T O U T

4 4 P S I G

L E A D S Y S T E M

S Y S 1

S Y S 1 C O M P R E S S O R

O N

S Y S 1 M O T O R A M P S

7 4 % F L A

S Y S 1 S U C T I O N P R E S S

5 9 P S I G

S Y S 1 D S C H P R E S S

2 2 0 P S I G

C O N T R O L T Y P E

L C H W T

S Y S 1 O I L P R E S S U R E

7 0 P S I D

C O O L I N G R A N G E

4 5 . 0 T O 4 7 . 0 D E G F

E N T E R I N G C O N D W A T E R

8 0 . 1

L E A V I N G C O N D W A T E R

9 0 . 5

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This message indicates SYS 2 discharge pressure atthe time of the fault.

This display shows the oil pressure of SYS 2 at the timeof the fault.

This display informs the operator whether SYS 2 liquidline solenoid was energized (ON) or de-energized (OFF)at the time of the fault.

This message informs the operator if SYS 2 Run Per-missive (flow switch, remote START/STOP) was in theRUN mode (ON) or STOP mode (OFF).

This message indicates the number of stages which wereloaded on SYS 2 at the time of the fault.

This display indicates the number of fans on SYS 2 whichwere running forward at the time of the fault.

This message indicates the number of fans on SYS 2which were running in the reverse direction at the time ofthe fault.

This display indicates whether the Hot Gas SolenoidValve was energized on SYS 2 at the time of the fault.

NOTE: The micro will attempt to control the Hot GasSolenoid Valve regardless of whether the optionis installed.

S Y S 2 O I L P R E S S U R E

7 4 P S I D

S Y S 2 L I Q L I N E

O N

S Y S 2 R U N P E R M I S S I V E

O N

S Y S 2 L O A D I N G S T A G E S

1

S Y S 2 F O R W A R D F A N S

O F F

S Y S 2 S U C T I O N P R E S S

6 2 P S I G

S Y S 2 R E V E R S E F A N S

O F F

S Y S 1 D S C H P R E S S

2 4 0 P S I G

S Y S 1 H O T G A S V A L V E

O F F

This display informs the operator whether SYS 1 liquidline solenoid was energized (ON) or de-energized (OFF)at the time of the fault.

This message informs the operator if SYS 1 Run Per-missive (flow switch, remote START/STOP) was in theRUN mode (ON) or (STOP) mode (OFF).

This message indicates the number of stages which wereloaded on SYS 1 at the time of the fault.

This display indicates the number of fans on SYS 1 whichwere running forward at the time of the fault.

This message indicates the number of fans on SYS 1which were running in the reverse direction at the time ofthe fault.

This display indicates whether the Hot Gas SolenoidValve was energized on SYS 1 at the time of the fault.

NOTE: The micro will attempt to control the Hot GasSolenoid Valve regardless of whether the optionis installed.

This message indicates whether Compressor 2 was ONor OFF at the time of the fault.

This message indicates SYS 2 motor current at the timeof the fault.

This display shows the suction pressure of SYS 2 at thetime of the fault.

S Y S 1 F O R W A R D F A N S

2

S Y S 1 R E V E R S E F A N S

O F F

S Y S 1 H O T G A S V A L V E

O F F

S Y S 2 C O M P R E S S O R

O F F

S Y S 2 M O T O R A M P S

6 0 % F L A

S Y S 1 L I Q L I N E

O N

S Y S 1 R U N P E R M I S S I V E

O N

S Y S 1 L O A D I N G S T A G E S

1

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UNIT ON/OFF SWITCH

A master UNIT ON/OFF switch is located on the key-pad. This rocker switch allows the operator to turn theentire chiller OFF if desired. The switch must be placedin the ON position for the chiller to operate.

Whenever the switch is placed in the OFF position, aSTATUS display indicating the condition will be displayed.This message is shown below.

SYSTEM SWITCHES

SYSTEM SWITCHES 1-4 are located on the Micropro-cessor Board (See Fig. 21). These allow the operator toselectively turn a given system on or off as desired. On a2 system chiller, switches 3 & 4 should be OFF. TheSystem Switch for a designated system must be ON(Switch to right) for the system to operate.

Whenever a switch is placed in the OFF position, a STA-TUS display indicating the condition will be displayedindicating that the system does not have a Run Permis-sive signal. A sample of this message is shown below.

NOTE: This message will not appear if Anti-recycle orAnti-coincident timers are in effect and are be-ing displayed.

UNIT ON/OFF SWITCH

UNITON / OFFSWITCH

U N I T S W I T C H I S I N

T H E O F F P O S I T I O N

S Y S # 1 N O R U N P E R M

S Y S # 2 N O R U N P E R M

ALARM CONTACTS (ANNUNCIATION ALARM)

*Dry contacts connected to terminals 23 and 24 (Fig.22) are supplied, which will transition to function as awarning whenever a fault shutdown occurs on any sys-tem or if power is lost to the control panel. The dry con-tacts are normally open (N.O.) and will close when con-trol power is applied to the panel, if no fault conditionsare present. If power is not lost or a fault lockout occurs,the contact will open.

A 28VDC or 120VAC external alarm circuit (by others)may be wired into the YORK supplied alarm contacts.Any inductive load devices (relay, contactor), suppliedby the user which are connected to the dry contacts,MUST be suppressed at the load. Use YORK P/N 031-00808-000 suppressor (not supplied). Failure to do thiswill result in nuisance faults and possible damage to thechiller.

CAUTION: If the alarm circuit is applied in an applica-tion used for critical duty (such as processduty or cooling other critical equipment) andthe alarm circuit should fail to function,YORK will not be liable for damages.

LEAD/LAG COMPRESSOR SELECTION

The Chiller may be set up for AUTO or MANUAL Lead/Lag. This is accomplished by properly configuring theS1 Dip Switches on the Microprocessor Board. Detailsfor configuring the switches are discussed in the DIS-PLAY KEY Section of the IOM under the OPTIONSkey.

02711TG

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FIG. 21 LOCATION OF THE MICROPROCESSOR BOARD

FIG. 22 ALARM CONTACT CONNECTION LOCATION

LD02092

26001ASYSTEM SWITCHES 1-4ON MICROPROCESSOR BOARD

MICROPROCESSORBOARD

When AUTO Lead/Lag is utilized, the micro attempts tobalance run time between the two compressors. A num-ber of conditions can occur which will prevent this fromhappening. Factors determining lead/lag selection andthe resulting lead/lag determination are discussed be-low:

1. The micro automatically defaults the lead to SYS 1and the lag to SYS 2 if both compressors are readyto start (Anti-recycle Timers timed out) and com-pressors have equal run time.

2. If both compressors are ready to start (Anti-recycleTimers timed out), the compressor with the lowestrun hours will start first.

3. If both compressors are waiting to start (Anti-recycleTimers are not timed out), the micro will assign thelead to the compressor with the shortest anti-recycletime in an effort to provide cooling quickly.

4. If the lead compressor is locked out, faulted andwaiting to restart, SYS switch on the micro board isoff, or a run permissive is keeping an individual sys-tem from running, the lag compressor is swapped tothe lead. This is true regardless of whether the lagcompressor is on or off.

If MANUAL Lead/Lag is selected, an external dry con-tact (switch) must be wired into the chiller. This contactis field supplied. With the contact open, SYS 1 is placedin the lead. When the contact is closed, SYS 2 will bethe lead system.

Manual Lead/Lag selection will be automatically overrid-den by the micro to allow the lag compressor in a mod-

28697A

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To disable the clock, place the jumper (Fig. 24) in theOFF positions, To activate it, place the jumper in the ONposition.

On power-up, the microprocessor will check the RealTime Clock (RTC Chip) battery to assure that the inter-nal battery is still operational. This is accomplished byperforming an RTC RAM location check. As long as thebattery checks out, the microprocessor will continue onwith business without interruption.

If a check is made and the battery has failed, the micro-processor will not allow the chiller to run and the follow-ing STATUS message will appear:

The only way to run the chiller is to press the MANUALOVERRIDE key. Under low battery conditions, the manualoverride key will function differently than it normally doesin service situations where it overrides the daily sched-ule for only 30 min. In a low battery condition, theMANUAL OVERRIDE key will zero out the daily sched-ule to allow unlimited operation regardless of the time onthe internal clock. Default values will also be loaded intomemory for all setpoints and cut-outs. These may re-quire reprogramming to assure they meet chiller operat-

ule to automatically become the lead anytime the se-lected lead compressor shuts down due to a lockout,lead system faults and is waiting to restart, lead systemswitch on the micro board is in the OFF position, or if arun permissive is keeping the lead system off. Automaticswitchover in the MANUAL mode is provided to try tomaintain chilled liquid temperature as close to setpointas possible.

The dry contact for manual lead/lag selection is wiredinto terminals 13 and 19 on the TB3 Terminal block. Thelocation of these terminals is shown in Fig. 23.

FIG. 23 LEAD/LAG CONTACT CONNECTION LOCATION

LD02093

26001AFIG. 24 CLOCK JUMPER

CLOCK JUMPER

! ! W A R N I N G ! !

! ! L O W B A T T E R Y ! !

MEMORY BATTERY BACK-UP

The Microprocessor board contains a Real Time Clock(RTC) I.C. Chip with an internal battery back-up. Thebattery back-up assures that any programmed values,clock, all fault information, accumulated information suchas starts/run time, etc. stored in the RTC memory is notlost when a power failure occurs regardless of the timeperiod.

The battery is a 10-year lithium type. The life of the bat-tery with power removed will depend upon whether theReal Time Clocks internal clock circuit is energized.With the clock OFF, approximately 10 years can be ex-pected, with the clock ON, approximately 5 years.

The clock is turned ON and OFF by a jumper on theMicroprocessor Board. While a chiller is operating, theclock must be ON. Otherwise the internal clock on themicroprocessor will not be active and the micro cannotkeep track of time, although all other functions will oper-ate normally. This could result in the chiller not startingdue to the time frozen on the clock falling outside theSTART/STOP time window that is programmed in theDAILY SCHEDULE.

If the chiller is shut down for extended periods of months,it may be desirable to disable the clock to save batterylife. The clock can then be reactivated and reprogrammedwhen the chiller is returned to service.

NOTE: ALL PROGRAMMED VALUES AND STOREDDATA, OTHER THAN THE INTERNAL CLOCKTIME-KEEPING, WILL BE MAINTAINED INMEMORY REGARDLESS OF WHETHER THECLOCK IS ON OR OFF AND REGARDLESSOF THE LENGTH OF THE POWER FAILURE.

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EMS/BAS CONTROLS

The microprocessor is capable of REMOTE START/STOP, REMOTE UNLOADING (Pulldown demand limit-ing), and REMOTE SETPOINT RESET. These functionscan be easily utilized by connecting use supplied drycontacts to the terminals on the TB3 Terminal Block.

REMOTE START/STOP BY A CYCLING DEVICE ORTIME CLOCK

Remote START/STOP is accomplished by connecting atime clock or other dry contact in series with the flowswitch on terminals 13 & 14. See Fig. 12 for the locationof the terminals. The contact must be closed to allowthe chiller to run. Any time the contact opens, the chillerwill shut down and the following status message will bedisplayed.

Wiring from these contacts should not exceed 25 ft. andshould be run in grounded conduit that does not carryany wiring other than control wiring. Additionally, if aninductive device (relay, contactor) is supplying thesecontacts, the coil of the device must be suppressed witha user supplied YORK P/N 031-00808 suppressor.

REMOTE SETPOINT RESET(REMOTE RESET TEMP RANGE)

Remote Setpoint Reset allows resetting the setpointupward from the programmed value in memory. This isaccomplished by connecting a dry contact betweenterminals 13 & 17. See Fig. 12 for the location of theseterminals. Closing the contact for a defined period of timeallows reset of the setpoint upward by up to 40°F (22.2°C)above the setpoint programmed in memory.

The maximum desired reset must be programmed intomemory and can be a value of 02 to 40°F (1.1 - 22.2°C).This value will vary according to the users requirements.To program the reset, press the REMOTE SETPOINTTEMP RANGE key. The following message will appear.

The display will indicate the REM SETPOINT which isalways equal to the chilled liquid setpoint plus the offsetfrom the reset signal. The display will also show theREM RANGE which is the same as the maximum resetrequired. Key in the maximum reset for the REM RANGEand press the ENTER Key to store the new value inmemory.

S Y S # 1 N O R U N P E R M

S Y S # 2 N O R U N P E R M

R E M S E T P O I N T = 4 0 . 0

R E M R A N G E = 2 0 D E G F

ing requirements. In addition, the low battery messagewhich is displayed for this condition will disappear.

NOTE: If a power failure should again occur, the aboveprocess will again need to be repeated to bringthe chiller back on line.

In the unlikely event the low battery message shouldever appear, it will require the RTC Chip U13 on the Mi-croprocessor Board (Fig. 13 to be replaced. Care shouldbe taken to assure that the chip is properly installed.Pin 1 (dimple in the top of the chip) must be oriented asshown (Fig. 13. The part number for the RTC Chip is031-00955-000.

CRANKCASE HEATER

The crankcase heater for a compressor will be ON when-ever the compressor is not running. The heater is inter-locked into the compressor motor contactor and is notcontrolled by the microprocessor.

The purpose of the crankcase heater is to prevent themigration of refrigerant to the crankcase during shutdownassuring proper lubrication of the compressor on start-up.

Anytime power is removed from the chiller for more thanan hour, the crankcase heater should be left on for 24hours prior to start. This can be accomplished by apply-ing 115VAC to the control panel.

EVAPORATOR HEATER

The evaporator heater prevents water standing in theevaporator from freezing. Whenever outdoor ambient tem-perature drops below 40°F (4.4°C), the microprocessorwill turn the evaporator ON. If temperature rises above45°F (7.2°C) the heater will be turned off.

METRIC DISPLAY

The control panel is capable of providing displays of pres-sure and temperature in metric values. Temperatures willbe displayed in °C and pressures in kPa.

A Metric to English temperature conversion table is pro-vided on the rear cover of this manual. Pressure can beconverted from PSI to kPa using the formula PSI x 6.89= kPa.

To obtain panel displays in metric, Switch 5 of Dip SwitchS1 on the Microprocessor Board must be placed in theOPEN position (Page 35). The positioning of this switchcan then be verified by pushing the OPTIONS key andverifying that METRIC UNITS READOUT is programmed(Page 35).

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Once the maximum reset is programmed, it will requirea contact closure of 21 seconds to achieve the maxi-mum reset. Closure for less than 21 seconds will providea smaller reset. For noise immunity, the micro will ig-nore closures of less than 1 second.

To compute the offset for a given timer closed, use theformula below:

1. Programmed max. reset20 seconds = Reset per sec.

2. (Time Closed - 1) Reset per sec. = Reset

Example:

Programmed max reset = 30°; Time Closed = 9 sec.

1. 30°= 1.5° per sec.

20 sec.

2. (9 sec. -1 sec.) 1.5° per sec. = 12° = Reset

To determine the new setpoints, add the reset to thesetpoint programmed into memory. In the example above,if the programmed setpoint = 44°F, the new setpoint af-ter the 9 second contact closure would be 44°F + 12°F= 56°F. This new setpoint can be viewed on the displayby pressing the REMOTE RESET TEMP/RANGE key.

To maintain a given offset, the micro must be refreshedevery 30 seconds - 30 minutes with a contact closure ofthe required time period. It will not accept a refresh soonerthan 30 seconds after the end of the last PWM signal,but must be refreshed before a period of 30 minutes ex-pires from the end of the last PWM signal.

After 30 minutes, if no refresh is provided, the setpointwill change back to its original value. A refresh is nothingmore than a contact closure for the period required forthe desired offset.

NOTE: After an offset signal, the new setpoint may beviewed on the REMOTE RESET TEMP RANGEDISPLAY However, if this display is being viewedwhen the reset pulse occurs, the setpoint willnot change on the display. To view the new off-set, first press any other display key on the key-pad and then press the REMOTE RESET TEMPRANGE key. The new setpoint will then appear.

Wiring from these contacts should not exceed 25 ft. andshould be run in grounded conduit that does not carryany wiring other than control wiring. Additionally, if aninductive device (relay, contactor) is supplying these con-tacts, the coil of the device must be suppressed with auser supplied YORK P/N 031-00808 suppressor.

NOTE: Remote Setpoint Reset will not operate when aRemote Control Center Option Kit is connectedto the Micro Panel, The Remote Control Centerwill always determine the setpoint.

REMOTE UNLOADING

The microprocessor is capable of remote unloading orpulldown demand limiting in two steps. The first stepshuts down the lag system. The second step unloadsthe lead system to its minimum step of capacity whichplaces the entire system at minimum possible capacity.

To shut down the lag compressor, a dry contact shouldbe connected between terminals 13 & 16. See Fig. 12for the location of these terminals. When the contact isclosed, the lag compressor will shut down.

Before the lead system can be unloaded to its minimumstep of capacity, the lag compressor must already bedisabled with a dry contact closure between terminal13 & 16 as described in the preceding paragraph.

With contacts on Terminals 13 & 16 closed, the leadsystem can be unloaded to its minimum step of capac-ity by closing a dry contact connected between termi-nals 13 & 17. See Fig. 12 for location of this terminal.The lead system will remain totally unloaded as long asthe contacts remain closed on both 13 & 16 and 13 &17. It should be noted that terminals 13 & 17 are nor-mally used for Remote Setpoint Reset. However, it isassumed that if the lag system is purposely being shutdown, Remote Setpoint Reset and temperature controlis of no importance. This is generally true since capacitycontrol of the load is lost when a large portion of thecapacity is disabled.

CAUTION: Two cautions should be observed when us-ing these functions. Observing these cau-tions will assure that undesirable operationdoes not result.

1. Terminals 13 & 17 contact should alwaysbe closed after or simultaneous with thoseon 13 & 16, when unloading of the lead sys-tem is desired. Otherwise, the microproces-sor may mistake the closed contacts on 13& 17 as a signal for a setpoint reset.

2. Terminal 13 & 17 contact should always beopened before or simultaneous with thoseon 13 & 16 when loading is desired. Other-wise, the microprocessor may mistake theclosed contacts on 13 & 17 as a signal fora setpoint reset.

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SYS. 1 SYS. 2 AMBIENT AMBIENT

FANS FANS ON OFF

1 & 2 3 & 4 25°F (-3.9°C) 24°F (-4.4°C)

5 & 6* 5 & 6* 45°F (7.2°C) 40°F (4.4°C)

* These fans will operate when either system is running and theambient is above 45°F (7.2°C).

FIG. 25 FAN LOCATIONS

STANDARD AMBIENT FAN CONTROL(ABOVE 25°F [-3.9°C])

Standard Ambient fan control above 25°F (-3.9°C) canbe selected by placing S1, Dip Switch 2 on Micropro-cessor Board in the OPEN position (See page 28).

Above 25°F, fans can either be controlled by ambienttemperature (Ambient and Discharge Pr Fan Control)or solely by discharge pressure control (Discharge Pres-sure Fan Control). This is selected by the operatorthrough S1, Dip Switch 8 on the Microprocessor Board(See page 34). Each of these methods of operation willbe discussed below. The contactor which activates thefans is noted in the description of operation (i.e. 5M).System fan location is shown in Fig. 25.

Ambient and Discharge Pr Fan Control

This control mode can be selected by placing S1, DipSwitch 8 on the Microprocessor Board in the OPENposition (See page 34). In Standard Ambient Fan Con-trol (operation at temperatures above 25°F [-3.9°C] only),discharge pressure will have no effect when operating inthe Ambient and Discharge Pr Fan Control mode. Inthis mode, fan control will be a function of ambient tem-perature only.

1. Fans 1 (5M) & 2 (7M) of SYS 1 or fans 3 (11M) & 4(13M) of SYS 2 will run when the ambient is above25°F (-3.9°C) and the respective system has run for aperiod of of 4 sec. These fans will continue to run untilthe system shuts down at 25°F (-3.9°C).

2. Fans 5 (6M) of SYS 1 and 6 (12M) of SYS 2 will bothrun when the ambient is above 45°F (7.2°C) and ei-

Discharge Pressure Fan Control

This mode can be selected by placing S1, Dip Switch 8on the Microprocessor Board in the CLOSED position(See page 34). In Standard Ambient Fan Control above25°F (-3.9°C), fan control will be solely be dischargepressure.

1. Fans 5 (6M) of SYS 1 and 6 (12M) of SYS 2 will bothrun when either systems discharge pressure reaches320 PSIG (2.2 mPa). These fans are shared fans anddo not require the respective system to run. Thesefans will continue to operate until the discharge pres-sure of the sytem that turned the fans on drops to 120PSIG (827.4 kPa) or discharge pressure of the sys-tem that turned the fans on exceeds 340 PSIG (2.3mPa).

2. Fans 1 (5M) and 2 (7M) or SYS 1 or fans 3 (11M) and4 (13M) of SYS 2 will run when the discharge pres-sure of the respective system reaches 340 PSIG (2.3mPa). These fans will continue to run until the dis-charge pressure drops below 120 PSIG (827.4 kPa).

3. Fans 5 (6M) or SYS 1 and 6 (12M) of SYS 2 will bothrun when the discharge pressure of either systemreaches 360 PSIG (2.5 mPa). These are shared fansand do not require the respective system to run. Op-eration of either system will activate both fans. Thesefans will operate until the discharge pressure drops to140 PSIG (965.3 kPa) on the system which activatedthe fans.

LD02699

ther system is running. These fans are shared fansand do not require the respective system to run. Op-eration of either system will activate both of thesefans, after one of the systems has run for a period of30 sec. These fans will continue to run until the ambi-ent drops below 40°F (4.4°C).

SYS. 1 SYS. 2

FANS FANSON OFF

5 & 6** 5 & 6** 320 PSIG (2.2 mPa) 120 PSIG (827.4 kPa)

1 & 2 3 & 4 340 PSIG (2.3 mPa) 120 PSIG (827.4 kPa)

5 & 6** 5 & 6** 360 PSIG (2.5 mPa) 140 PSIG (965.3 kPa)

** These fans will operate when discharge pressure of eithersystem reaches 360 PSIG (2.5 mPa).

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LOW AMBIENT CONTROL

The chiller is designed to operate in low ambients downto 0°F (-17.8°C) by merely placing S1, Dip Switch 2 onthe Microprocessor Board in the CLOSED position(See page 28) and reprogramming the low ambient cut-out, page 35, to the desired cut-out point.

NOTE: Occasional operation below 0°F (-17.8°C) is nor-mally possible. In these situations, low suctionpressure shutdowns may sometimes occur. A cut-out of 0.00°F will allow operation in ambients below0°F (-17.8°C).

The fundamental purpose of the Low Ambient Controlmode is to reduce the condenser capacity when theambient is in the 0 - 25°F (-17.8 to -3.9°C) temperaturerange. This assures that adequate discharge pressurescan be maintained at low ambient temperatures whichwill eliminate low suction pressure faults. Operation atlow ambients is accomplished by cycling fans acordingto discharge pressure. When the micro is programmedfor the low ambient mode, an extra step of fan cycling isautomatically added.

The fans can be controlled by a combination of ambientand discharge pressure control or solely by dischargepressure control.

Ambient and Discharge Pr Fan Control0 - 25°F (-17.8 to -3.9°C)

To operate the fans throughout the entire ambient rangeby a combination of both ambient and discharge pres-sure, the S1, Dip Switch 8 on the Microprocessor Boardmust be placed in the OPEN position.

Fan operation below 25°F (-3.9°C) is controlled only bydischarge pressure. 4 steps of fan operation will operateas follows:

1. Until discharge pressure reaches 320 PSIG (2.2 mPa)on one of the systems, all fans will remain off.

2. Fans 5 (6M) of SYS 1 and 6 (12M) of SYS 2 will bothrun when the ambient is below 25°F (-3.9°C) and ei-ther systems discharge pressure reaches 320 PSIG(2.2 mPa). These fans are shared fans and do notrequire the respective system to run. These fans willcontinue to operate until the discharge pressure ofthe system that turned the fans on drops to 120 PSIG(827.4 kPa), the ambient temperature rises above 35°F(1.7°C), or discharge pressure of the system thatturned the fans on exceeds 340 PSIG (2.3 mPa).

3. If the discharge pressure of the system that turnedfans 5 and 6 on rises to 340 PSIG (2.3 mPa), fans 5and 6 will shut off and SYS 1 fans 1 (5M) and 2 (7M)or SYS 2 fans 3 (11M) and 4 (13M) will turn on. Thesefans will stay on until discharge pressure of the re-spective system drops to 120 PSIG (827.4 kPa).

NOTE: If the other systems discharge pressure ex-ceeds 320 PSIG (2.2 mPa), fans 5 & 6 willcontinue to run.

4. The final stage of fan control will operate fans 5 (6M)and 6 (12M) when the discharge pressure of eithersystem reaches 360 PSIG (2.5 mPa). These fans willremain on until the discharge pressure of the systemthat turned the fans on falls to 140 PSIG (965.3 kPa).

LOW AMBIENT MODE FAN CYCLING (Ambient Temperature / Discharge Pressure Control)

CONTROL BYTEMPERATURE & PRESSURE

SYS FAN CONTACTOR BELOW 25°F (-3.9°C) ABOVE 25°F (-3.9°C) PRESSURE CONTROL TEMPERATURE CONTROL ONLY

ON OFF ON OFF

5 & 6 6M & 12M320 PSIG 120 PSIG (827.4 kPa) Will Not Start 35°F (1.7°C) or(2.2 mPa) or 340 PSIG (2.3 mPa) Above 25°F (-3.9°C) 340 PSIG (2.3 mPa)

Turns OFF by1

1 & 2 5M & 7M340 PSIG 120 PSIG

25°F (-3.9°C)Pressure

(2.3 mPa) (827.4 kPa) Only at 120 PSIG(827.4 kPa)

5 & 6 6M & 12M 360 PSIG (2.5 mPa) 140 PSIG (965.3 kPa) 45°F (7.2°C) 40°F (4.4°C)

5 & 6 6M & 12M320 PSIG 120 PSIG (827.4 kPa) Will Not Start 35°F (1.7°C) or(2.2 mPa) or 340 PSIG (2.3 mPa) Above 25°F (-3.9°C) 340 PSIG (2.3 mPa)

Turns OFF by2

3 & 4 11M & 13M340 PSIG 120 PSIG

25°F (-3.9°C)Pressure

(2.3 mPa) (827.4 kPa) Only at 120 PSIG (827.4 kPa)

5 & 6 6M & 12M 360 PSIG (2.5 mPa) 140 PSIG (965.3 kPa) 45°F (7.2°C) 40°F (4.4°C)

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Ambient and Discharge Pr Fan ControlAbove 25°F (-3.9°C)

Fan operation above 25°F (-3.9°C) will primarily be byambient temperature except for situations where tem-peratures rose from the low ambient range to above 25°F(-3.9°C) and situations where fans are operating and dis-charge pressures drop very low as ambients fall below25°F (-3.9°C).

1. Fans 1 (5M) and 2 (7M) of SYS 1 or fans 3 (11M) and4 (13M) of SYS 2 will run when the ambient is above25°F (-3.9°C) and the respective system has run for aperiod of 4 sec. These fans will continue to run untilthe system shuts down at 25°F (-3.9°C).

2. Fans 5 (6M) of SYS 1 and 6 (12M) SYS 2 will both runwhen the ambient is above 45°F (7.2°C) and eithersystem is running. These fans are shared fans and donot require the respective system to run. Operation ofeither system will activate both of these fans, afterone of the systems has run for a period of 30 sec.These fans will continue to run until the ambient dropsbelow 40°F (4.4°C).

If fans 5 and 6 were the only fans running as tempera-tures rose from below 25°F (-3.9°C) to above 25°F (-3.9°C),the fans would continue to run until the ambient rose to35°F (1.7°C) or discharge pressure of the system thatcaused the fans to start rose to 340 PSIG (2.3 mPa). Ineither case, fans 1 and 2 of SYS 1 and/or fans 3 and 4 ofSYS 2 will come on if the system is running.

If fans 1 and 2 SYS 1 or fans 3 or 4 SYS 2 are runningand ambient is above 25°F (-3.9°C), the fans will con-tinue to run as ambient drops below 25°F (-3.9°C) untilthe system shuts down or the systems discharge pres-sure drops below 120 PSIG (827.4 kPa).

Discharge Pressure Fan Control(All Temperatures in Low Ambient Mode)

Fan operation in this mode will be solely by dischargepressure. 4 steps of fan operation will be noted. Thismode may be selected by placing S1, Dip Switch 8 onthe Microprocessor Board in the CLOSED position (Seepage 36).

1. Until discharge pressure reaches 320 PSIG (2.2 mPa)on one of the systems, all fans will remain off.

2. Fans 5 (6M) of SYS 1 and 6 (12M) of SYS 2 will bothrun when either systems discharge pressure reaches320 PSIG (2.2 mPa). These fans are shared fans anddo not requrie the respective system to run. Thesefans will continue to operate until the discharge pres-

sure of the system that turned the fans on drops to120 PSIG (827.4 kPa) or discharge pressure of thesystem that turned the fans on exceeds 340 PSIG(2.3 mPa).

NOTE: These fans may continue to run if the sys-tem that has not yet reached a discharge pres-sure of 340 PSIG (2.3 mPa) is operating at adischarge pressure above 340 PSIG (2.3mPa).

3. Fans 1 (5M) and 2 (7M) of SYS 1 or fans 3 (11M) and4 (13M) of SYS 2 will run when the discharge pres-sure of the respective system reaches 340 PSIG (2.3mPa). These fans will continue to run until the dis-charge pressure drops below 120 PSIG (827.4 kPa).

4. Fans 5 (6M) of SYS 1 and 6 (12M) of SYS 2 will bothrun when the discharge pressure of either systemreaches 360 PSIG (2.5 mPa). These are shared fansand do not require the respective system to run. Op-eration of either system will activate both fans. Thesefans will operate until the discharge pressure drops to140 PSIG (965.3 kPa) on the system which activatedthe fans.

CONTROL BYPRESSURE ONLY

SYS FAN CONTACTOR TEMPERATUREHAS NO EFFECT

ON OFF

1 & 3 REV 9M & 10M320 PSIG 120 PSIG (827.4 kPa)(2.2 kPa) or 340 PSIG (2.3 mPa)

12 & 4 6M & 8M

340 PSIG 120 PSIG(2.3 mPa) (827.4 kPa)

1 & 3 FWD 5M & 7M 360 PSIG (2.5 mPa) 140 PSIG (965.3 kPa)

5 & 7 REV 15M & 16M320 PSIG 120 PSIG (827.4 kPa)(2.2 mPa) or 340 PSIG (2.3 mPa)

320 PSIG 120 PSIG2 6 & 8 12M & 14M

(2.2 mPa) (827.4 kPa)

5 & 7 FWD 11M & 13M 340 PSIG (2.3 mPa) 140 PSIG (965.3 kPa)

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COMPRESSOR CAPACITY CONTROL

FIG. 26 COMPRESSOR UNLOADING SEQUENCE

CHILLER# OF

# OFMODEL SYSTEM

CYLINDERSUNLOADING STEPS

YCA STANDARDJ110 1 6J120

2 65

J130

4 CYLINDER

LD02754

The function of the compressor capacity control systemis to automatically adjust the compressor pumping ca-pacity to balance with the cooling load at a pre-deter-mined return water temperature and to permit the com-pressor to start under partial load. The compressor ca-pacity control system is actuated by means of gas pres-sure from the discharge side of the compressor. Gaspressure to the unloader piston unloads the associatedcylinders, and release of this pressure loads them. Con-trol of the gas pressure to the unloader elements is thefunction of the compressor capacity control solenoids.

UNLOADING

When the solenoid valve is energized, discharge gas pres-sure is applied to the top of the unloader piston, forcingit down. The bottom end of the piston seats against therecessed opening to the suction plenum, effectively block-ing the flow of suction gas into the cylinders (blockedsuction unloading). The cylinders are now unloaded.

LOADING

When the solenoid valve is de-energized, gas pressureon top of the unloader piston is relieved to the suctionplenum. This forces the piston up, uncovering the re-cessed opening which allows the suction gas to flowthrough the port and into the cylinders. The cylindersare now loaded.

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SYSTEM START-UP CHECKLIST

CHECKING THE SYSTEM 24 HOURS PRIOR TOINITIAL START-UP (NO POWER)

JOB NAME: __________________________________SALESORDER #: ___________________________________

LOCATION: __________________________________

SOLD BY: ___________________________________

INSTALLINGCONTRACTOR: ______________________________

STARTUP: ___________________________________TECHNICIAN/COMPANY: __________________________________

DATE: ______________________________________

CHILLER

MODEL #: _________________________________

SERIAL #: _________________________________

COMPRESSOR #1

MODEL #: _________________________________

SERIAL #: _________________________________

COMPRESSOR #2

MODEL #: _________________________________

SERIAL #: _________________________________

Unit Checks

9 1. Inspect the unit for shipping or installation dam-age.

9 2. Assure that all piping has been completed.

9 3. Check that the unit is properly charged andthat there are no piping leaks.

9 4. Suction and discharge stop valves and the re-frigerant liquid stop valves are open (ccw).

CAUTION: Compressor lubrication circuit must beprimed with YORK C oil prior to start-up.Priming should be done through theSchrader fitting at the compressor oil pump.Stroke oil pump 10 times to prime the lubri-cation circuit.

9 5. The compressor oil level must be maintainedbetween the middle of the upper and middle ofthe lower sight glass at all operating condi-tions. At part load operating conditions, it isnot abnormal for the oil level to be in the lowersight glass. If it is necessary to add oil, con-nect a YORK oil pump to the oil charging valve,but do not tighten the flare nut on the deliverytubing. With the bottom (suction end) of thepump submerged in oil to avoid the entrance ofair, operate the pump until oil drips from theflare nut joint, allowing the air to be expelled,and tighten the flare nut. Open the compres-sor oil charging valve and pump in oil until theoil reaches the proper level as described above.Close the compressor oil charging valve.

9 6. Assure water pumps are on. Check and adjustwater pump flow rate and pressure drop acrosscooler.

9 7. Check panel to see that it is free of foreignmaterial (wires, metal chips, etc.).

9 8. Visually inspect wiring (power & control). Mustmeet NEC and all local codes.(See Fig. 10 & 12)

9 9. Check for proper size fuses in main and con-trol power circuits.

9 10. Verify that field wiring matches the 3-phasepower requirements of the compressor. Seenameplate. (See Fig. 10)

9 11. Assure 115VAC Control Power to TB1 has 30Aminimum capacity. (See Fig. 10)

9 12. Be certain all control bulbs are inserted com-pletely in their respective wells and are coatedwith heat conductive compound.

PANEL CHECKS (POWER ON, BOTH SYSTEMSWITCHES OFF)

9 1. Apply 3-phase power and verify its value. (SeeFig. 10). φ A: ____, φ B: ____, φ C: ____ VAC

9 2. Apply 115VAC and verify its value on the termi-nal block in the lower left of the Power Panel.Make the measurement between terminals 5and 2. Should be 115VAC ± 10%. (See Fig.10). ______ VAC

9 3. Assure crankcase heaters are on. Allow crank-case heaters to remain on a minimum of 24

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hours before start-up. This is important to as-sure no refrigerant is in the oil at start-up!

9 4. Program the Dip Switches on the Micropro-cessor Board (Page 34) and verify the selec-tion by pressing the OPTIONS key.Switch 3 should always be closed.Switch 6 should always be open.

NOTE: It is IMPORTANT that all switches are properlyprogrammed. Otherwise, undesirable operationwill result.

9 5. Press the PROGRAM key and program eachof the 11 limits and record them. They are asfollows:

9 Discharge Cutout ____PSIG

9 Outside Air Temp Low Cutout ____°F

9 Outside Air Temp High Cutout ____°F

9 Discharge Pressure Unload Pressure____PSIG

9 Suction Pressure Unload Pressure ____PSIG

9 Leaving Water Temp Cutout ____°F

9 Suction Pressure Cutout ____PSIG

9 Rate Control Temp ____°F

9 Anti Recycle Time ____SEC

9 Rate Sensitivity ____°F/MlN

9 Number of Load Steps ____

See page 41 for assistance in programmingthese values.

9 6. Program the date and time by first assuringthat the CLK jumper J18 on the Microproces-sor Board (Fig. 26) is in the ON position (Top 2pins).

Press the SET TIME key and set the date andtime (Page 45).

9 7. Program the Daily and Holiday Start/StopSchedule by pressing the SET SCHEDULE/HOLIDAY key (Page 46).

9 8. Program the Chilled Liquid Setpoint and Con-trol Range by pressing the CHILLED LIQUIDTEMP/RANGE key (Page 49).

9 9. If the Remote Reset is to be used, the maxi-mum reset must be programmed. This can beprogrammed by pressing the REMOTE RESETTEMP RANGE key (Page 72).

INITIAL STARTUP

After the operator has become thoroughly familiar withthe control panel and has performed the preceedingchecks 24 hours prior to startup, the unit can be put intooperation.

9 Place the System Switches to the ON position.See the OPERATING SEQUENCE for unit opera-tion.

9 The compressor will start and a flow of liquid shouldbe noted in the liquid indicator. After several min-utes of operation, the bubbles will disappear andthere will be a solid column of liquid when the unitis operating normally. On startup, foaming of theoil may be evident in the compressor oil sightglass. After the water temperature has been pulleddown to operating conditions, the oil should beclear. Normal operation of the unit is evidencedby a hot discharge line (discharge superheatshould not drop below 50°F [10°C]), clear oil inthe compressor crankcase, solid liquid refriger-ant in the liquid indicator and usually no morethan 2 PSIG variation in suction pressure for anygiven set of operating conditions.

9 Allow the compressor to run for a short time, be-ing ready to stop it immediately if any unusualnoise or other adverse condition should develop.When starting the compressor, always make surethe oil pump is functioning properly. Compressoroil pressure must be as described in the SYS-TEM SAFETIES Section, page 57.

9 Check the system operating parameters. Do thisby selecting various readouts such as pressuresand temperatures. Compare these to test gaugereadings.

CHECKING SUPERHEAT AND SUBCOOLING

The subcooling should always be checked when charg-ing the system with refrigerant and/or before setting thesuperheat.

When the refrigerant charge is correct, there will be nobubbles in the liquid sightglass with the system operat-ing under full load conditions, and there will be 10°F to15°F (5.5 to 8.3°C) subcooled liquid refrigerant leavingthe condenser.

An overcharged system should be guarded against. Evi-dences of overcharge are as follows:

a. If a system is overcharged, the discharge pressurewill be higher than normal. (Normal discharge/con-densing pressure can be found in refrigerant tem-perature/pressure chart; use entering air tempera-ture +30°F (16.7°C) for normal condensing tem-peratures.)

b. The temperature of the liquid refrigerant out of thecondenser should not be more than 15°F (8.3°C)less than the condensing temperature. (The tem-perature corresponding to the condensing pressurefrom refrigerant temperature/pressure chart).

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The subcooling temperature should be taken by record-ing the temperature of the liquid line at the outlet of thecondenser and recording the liquid line pressure at theliquid stop valve with the system fully loaded after steadystate operation has been established and converting itto temperature from a temperature/pressure chart. Besure to insulate the thermometer or thermocouple at-tached to the piping.

Example:LIQUID LINE PRESSURE202 PSIG converted to 102°F(38.9°C)Minus Liquid Line Temperature - 90°F(32.2°C)

Subcooling = 12°F (6.7°C)

Record: SYS 1______, SYS 2______

The proper refrigerant charge is attained when subcoolingis measured at 10 - 15°F (5.6 - 8.3°C). Add charge asneeded to increase subcooling and remove charge asnecessary to reduce subcooling. Whenever removingcharge, be sure to recover it in an approved container.

After the subcooling is set at 10 - 15°F (5.6 - 8.3°C) byadding or removing charge and steady state fully loadedoperation is established, system superheat should alsobe adjusted for 10 - 15°F (5.6 - 8.3°C). A factory recom-mended superheat setting of 15°F (8.3°C) is appropriatefor systems that operate over a variety of ambient tem-peratures, chilled liquid temperatures, and loading con-ditions. It also compensates for gauge and temperaturesensor inaccuracy. When measuring superheat, be sureto insulate a thermometer or thermocouple attached tothe piping to assure a true temperature is measured.

The superheat is the difference between the actual tem-perature of the returned refrigerant gas entering the com-pressor and the temperature corresponding to the suc-tion pressure as shown in a standard pressure/tempera-ture chart. The suction temperature should be taken 6"before the compressor service valve, and the suction pres-sure is taken at the compressor suction service valve.

Example:Suction Temperature 46°F (7.8°C)Minus Suction Pressure - 56 PSIG

Converted to Temperature - 31°F (-0.6°C)Superheat = 15°F (8.3°C)

Superheat SYS 1 ____, SYS 2 ____

Normally, the thermal expansion valve need not be ad-justed in the field. If, however, an adjustment is to bemade, the expansion valve adjusting screw should beturned not more than one turn at a time, allowing suffi-cient time (approximately 15 minutes) between adjust-ments for the system and the thermal expansion valveto respond and return to settled operation.

Proper subcooling and superheat will assure optimumperformance and reliability of the system. Checks shouldalways be made when commissioning a chiller and on ayearly basis.

If the unit has been functioning satisfactorily during theinitial operating period, it is ready for continuous opera-tion.

9 Leak check compressors, fittings, and piping toassure no leaks are present from improper handling.

OPERATING SEQUENCE UTILIZINGRETURN WATER CONTROL

NOTE: The operating sequence described below relatesto operation after power has been applied on ahot water start such as startup commissioningor a hot water start at the beginning of the day.It also assumes that 10 steps of loading areavailable and programmed. If less than 10 stepsare available, no chiller response will take placeat some of the operating points described.

1. For the system compressors to run, all ManualReset Cutouts must be reset, the Flow Switchmust be closed, the System Switches must beON, the Daily Schedule must be scheduling thechiller to run, and temperature demand must bepresent.

2. As long as power is applied, the Crankcase Heat-ers will be on and stay on as long as the com-pressors are not running.

3. If power has just been applied to the system, themicroprocessor will start a 2 minute timer. This isthe same timer that prevents an instantaneousstart after a power failure.

NOTE: Compressor Crankcase Heaters shouldbe on for a period of 24 hours prior tocommissioning. Failure to allow theheater sufficient time to warm the oil maydamage the compressor due to liquid re-frigerant in the oil.

4. At the end of the 2 minute timer, the micropro-cessor will check for cooling demand as well ascheck to see if any system safeties have beenexceeded. If all conditions allow for start, the leadcompressor will start unloaded. Coincident withthe start, the programmable anti-recycle timer willbe set and begin counting downward to 0. Theliquid line solenoid of the compressor will open.

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5. After 4 seconds of run time, the motor currentof the lead compressor must be > 14% FLA and< 115% FLA. Oil pressure must be > 5 PSID (345kPa). If these conditions are not met, the leadcompressor will shut down.

6. After 30 seconds of run time, the oil pressureof the lead compressor must be > 20 PSID (137.9kPa) and the suction pressure must be > 50% ofcutout. If these conditions are not met, the leadcompressor will shut down.

7. After 1 minute of run time, the lead compres-sor will load the 1st step, if cooling demand (tem-perature and rate control) requires.

8. After 2 minutes of run time, the lead compres-sor will load the 2nd step, if cooling demand (tem-perature and rate control) requires.

9. After 3 minutes of run time, the lead compres-sor will load its 3rd step, if temperature demand(temperature and rate control) requires.

10. After 4 minutes of operation, the oil pressureof the lead compressor must be >25 PSID (172.4kPa) and the suction pressure must be > cutout.If these conditions are not met, the lead com-pressor will shut down. If cooling demand requires(temperature and rate control), the lag compres-sor will start unloaded and its anti-recycle counterwill begin counting back to 0. The liquid line so-lenoid will open. The lead compressor will unload2 steps to its 1st step of 3 loading steps.

11. After 4 minutes and 4 seconds of run time,the motor current of the lag compressor must be>14% FLA and < 115% FLA. Oil pressure mustbe > 5 PSID (34.5 kPa). If these conditions arenot met, the lag compressor will shut down.

12. After 4 minutes and 30 seconds of run time,the oil pressure of the lag compressor must be>20 PSID (137.9 kPa) and the suction pressuremust be > 50% cutout. If these conditions are notmet, the lag compressor will shut down.

13. After 5 minutes of run time, the lag compres-sor will load to the 1st step of loading, if coolingdemand requires (temperature and rate control).The lead compressor remains unchanged at the1st step of loading.

14. After 6 minutes of run time, the lead compres-sor will load to its 2nd step of loading, if coolingdemand requires (temperature and rate control).The lag compressor remains unchanged at the1st step of loading.

15. After 7 minutes of run time, the lag compres-sor will load to its 2nd step of loading, if coolingdemand requires.

16. After 8 minutes of operation, the oil pressureof the lag compressor must be > 25 PSID (172.4kPa) and the suction pressure must be > cutout .If these conditions are not met, the lag compres-sor will shut down (temperature and rate control).The lead compressor will load to its 3rd and finalstep of loading, if cooling demand requires (tem-perature and rate control). The lag compressorremains unchanged at the 2nd step of loading.

17. After 9 minutes of run time, the lag compres-sor will load its 3rd and final step, if cooling de-mand requires (temperature and rate control). Thelead compressor remains unchanged at the 3rdstep of loading.

OPERATING SEQUENCE UTILIZINGLEAVING WATER CONTROL

NOTE: The operating sequence described below relatesto operation after power has been applied on ahot water start such as at start-up commission-ing or a hot water start up at the beginning ofthe day. It also assumes that 10 steps of load-ing are available and programmed. If less than10 steps are available, no chiller response willtake place at some of the operating points de-scribed.

1. For the system compressors to run, all ManualReset Cut-outs must be reset, the Flow Switchmust be closed, any Remote Cycling Contractsmust be closed, the System Switches must beON, the Daily Schedule must be scheduling thechiller to run, and temperature demand must bepresent.

2. As long as power is applied, the Crankcase Heat-ers will be on and stay on as long as the com-pressors are not running.

3. If power has just been applied to the system, themicroprocessor will start a 2-minute timer. This isthe same timer that prevents an instantaneousstart after a power failure. NOTE: CompressorCrankcase Heaters should be on for a period of24 hours prior to commissioning. Failure to allowthe heater sufficient time to warm the oil maydamage the compressor due to liquid refrigerantin the oil.

4. At the end of the 2 minute timer, the micropro-cessor will check for cooling demand as well ascheck to see if any system safeties have been

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exceeded. If all conditions allow for start, the leadcompressor will start unloaded. Coincident withthe start, the programmable anti-recycle timer willbe set and begin counting downward to 0. Theliquid line solenoid of the lead compressor willopen.

5. After 4 seconds of run time, the motor currentof the lead compressor must be > 14% FLA and<115% FLA. Oil pressure must be > 5 PSID (34.5kPa). If these conditions are not met, the leadcompressor will shut down.

6. After 30 seconds of run time, the oil pressureof the lead compressor must be > 20 PSID (137.9kPa) and the suction pressure must be > 50% ofcut-out. If these conditions are not met, the leadcompressor will shut down.

7. After 2 minutes and 30 seconds of run time,the lead compressor will load the 1st step, if cool-ing demand (temperature and rate control) re-quires.

8. After 4 minutes of operation, the oil pressureof the lead compressor must be > 25 PSID (172.4kPa) and the suction pressure must be > cut-out.If these conditions are not met, the lead com-pressor will shut down.

9. After five minutes of run time, the lead com-pressor will load the second step, if cooling de-mand (temperature and rate control) requires.

10. After 7 minutes and 30 seconds of run time,the lead compressor will load its 3rd step, if tem-perature demand (temperature and rate control)requires.

11. After 10 minutes of run time, if cooling demandrequires (temperature and rate control), the lagcompressor will start unloaded and its anti-recyclecounter will begin counting back to 0. The liquidline solenoid will open. The lead compressor willunload two steps to its 1st step of 3 loading steps.

12. After 10 minutes and 4 seconds of run time,the motor current of the lag compressor must be> 14% FLA and < 115% FLA. Oil pressure mustbe > 5 PSID (34.5 kPa). If these conditions arenot met, the lag compressor will shut down.

13. After 10 minutes and 30 seconds of run time,the oil pressure of the lag compressor must be >20 PSID (137.9 kPa) and the suction pressuremust be > 50% cutout. If these conditions are notmet, the lag compressor will shut down.

14. After 12 minutes and 30 seconds of run time,the lag compressor will load to the 1st step ofloading, if cooling demand requires (temperatureand rate control). The lead compressor remainsunchanged at the 1st step of loading.

15. After 14 minutes of operation, the oil pressureof the lag compressor must be > 25 PSID (172.4kPa) and the suction pressure must be > cutout .If these conditions are not met, the lag compres-sor will shut down.

16. After 15 minutes of run time, the lead com-pressor will load to its 2nd step of loading, if cool-ing demand requires (temperature and rate con-trol). The lag compressor remains unchanged atthe 1st step of loading.

17. After 17 minutes and 30 seconds of run time,the lag compressor will load to its 2nd step ofloading, if cooling demand requires (temperatureand rate control). The lead compressor remainunchanged at the 2nd step on loading.

18. After 20 minutes of run time, the lead com-pressor will load to its 3rd and final step of load-ing, if cooling demand requires (temperature andrate control). The lag compressor remains un-changed at the 2nd step of loading.

19. After 22 minutes and 30 seconds of run time,the lag compressor will load to its 3rd and finalstep, if cooling demand requires (temperature andrate control). The lead compressor remains un-changed at the 3rd step of loading.

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PREVENTATIVE MAINTENANCE

It is the responsibility of the owner to provide the neces-sary daily, monthly and yearly maintenance requirementsof the system.

IMPORTANT

If a system failure occurs due to improper main-tenance during the warranty period; YORK willnot be liable for costs incurred to return the sys-tem to satisfactory operation. The following is in-tended only as a guide and covers only the chillerunit components. It does not cover other relatedsystem components which may or may not befurnished by YORK. System components shouldbe maintained according to the individualmanufacturers recommendations as their opera-tion will affect the operation and life of the chiller.

DAILY MAINTENANCE

It is recommended that the following items be checkeddaily.

1. Oil Level Correct oil level is when oil appears ineither of the compressor oil sight glasses after theunit has been in operation for about two hours. If it isnecessary to add oil after this operating period, seeitem #3 under the ANNUAL MAINTENANCE sec-tion.

2. Oil Pressure Oil pressure should be a minimum of50 PSI (344.7 kPa) above suction pressure. Typicalpressure is 65 - 70 PSI (448.2 to 482.6 kPa).

3. Compressor Superheat Correct superheat is 10 -15°F (5.6 to 8.3°C) measured at the compressor.

4. Operating Pressures and Temperatures Check tosee that operating pressures and temperatures arewithin the LIMITATIONS shown in this book.

WEEKLY MAINTENANCE

It is recommended that the following items be checkedweekly.

1. All items listed under DAILY MAINTENANCE.

2. Color of Compressor Oil New oil is clear, and if thesystem is not contaminated with moisture and/orforeign material, should retain its new appearance

for a reasonable length of operating time. Discolora-tion of the oil, either turning darker brown or in somecases lighter, is an indication of contamination, ba-sically due to moisture. If it is necessary to chargeoil refer to item #3 under the ANNUAL MAINTE-NANCE section.

3. Check the refrigerant circuit for leaks.

4. Operating Pressures and Temperatures Check tosee that operating pressures and temperatures arewithin the LIMITATIONS shown in this book.

ANNUAL MAINTENANCE

It is recommended that the following items be checkedannually.

1. All items under WEEKLY MAINTENANCE.

2. Operating Controls Check to see if controls areset and operating within the proper limits. See UnitControls and OPERATION section of this book.

3. Compressor Oil Drain, inspect and refill with newoil. This requires pumping out the compressor. Ifpossible, this should be done after the unit has beenin operation for some time, when the oil in the crank-case will contain the least amount of refrigerant. Topump out the compressor, proceed as follows:

A. Close the suction stop valve.

B. Open the discharge stop valve two turns of thestem.

C. Operate the compressor until 15 to 20 inches(381 to 508 mm) vacuum is obtained. Do this bydisconnecting the wiring to LLSV and repeat-edly starting the compressor. Recycle 115VACpower to the Logic Panel to reduce anti-recycletime to 2 minutes if needed. The compressorshould in no case be operated under vacuumconditions for longer than 10 to 15 seconds.

D. Stop the compressor and immediately close thedischarge stop valve. The procedures outlinedin steps (B) and (C) above should be repeated ifthe suction pressure rises rapidly to 15 PSIG(103.4 kPa) or more which would indicate con-siderable refrigerant remaining in the crankcaseoil. Do not expect to retain 0 PSIG since somerefrigerant will continually be released from theoil in the crankcase.

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E. After pumping down the compressor, wait untilthe pressure builds up to 2 or 3 PSIG beforeopening up any part of the hermetic compres-sor.

F. Open the coil drain valve slowly and drain asmuch oil from the compressor as possible.

G. Examine the oil for any metal particles whichwould indicate wear on the bearings, crankshaftor connecting rods. If metal particles are found,the need for closer examination by factory ser-vice personnel is indicated.

H. If the oil is clean and free of metal particles, refillthe compressor with YORK oil C. To add oil orto fill the compressor crankcase, connect thedelivery tube of the YORK Hand Oil Pump. YORKPart No. 470-10654 or equal to the compressoroil charging and drain valve. Expel all air fromthe delivery tube by pumping it full of oil, allowinga few drips to drip out before tightening the flarenut to the oil charging valve. Then open the oilcharging valve and pump oil into the crankcaseto the proper level. It is necessary that the suc-tion end of the hand oil pump be kept submergedunder the oil level in the container at all times, toavoid entrance of air into the compressor.

I. Before opening the suction or discharge stopvalves, connect a vacuum pump to the pumpoutport in the discharge stop valve. (Pumpout portis port on valve stem side of valve). With thevacuum line shutoff valve open, run the vacuumpump until a vacuum of at least 1000 microns isreached. Stop the vacuum pump, close the shut-off valve and open the discharge valve fully be-fore disconnecting the line from the vacuumpump. Disconnect the vacuum pump and replacethe plug in the pumpout port.

NOTE: If suction or discharge valves are not seatedproperly, a 1000 micron vacuum can not be ob-tained. Do not evacuate for long periods of time.

J. Be sure both discharge and suction stop valvesare open before operating the unit.

4. Suction and Discharge Valves and Springs - Thecondition of the suction and discharge valves andsprings should be checked by YORK service per-sonnel on a yearly basis or every 5000 hours, which-ever comes first.

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HOT GAS BYPASS (LOADMINDER) OPTION

General

The Hot Gas Bypass Option is available as a factoryinstalled option to prevent compressor cycling and watertemperature fluctuation at low load. This is accomplishedby providing further capacity reduction below the last stepof compressor cylinder unloading by introducing an arti-ficial load to the cooler, which keeps the compressor onthe line. The option will provide hot gas bypass on bothcompressors enabling hot gas to be active regardless ofwhich compressor is in the lead.

NOTE: The microprocessor will only activate the hot gason the lead compressor.

The hot gas bypass consists of a pilot operated regulat-ing valve with an integral solenoid. The pilot operatedsolenoid is controlled by the microprocessor accordingto water temperature. The regulating valve which becomesactivated when the solenoid is energized, is controlledby suction pressure to modulate the flow of gas in abypass connected from the compressor discharge to thecooler inlet. The following text will explain how the hotgas solenoid is activated by the microprocessor in bothreturn and in leaving water control.

LWT Control Hot Gas Operation

The hot gas solenoid is energized when the leaving wa-ter temperature falls below the Target water tempera-ture, if the compressor is on its minimum stage of load-ing. Hot gas may then be fed according to the suctionpressure and the pressure regulating valve setting. Onceactivated, the micro will keep the solenoid energized untilthe leaving water temperature rises above the high limitof the Control Range or until the load becomes so lowthat the hot gas can no longer keep temperature within

OPTIONS

This section is devoted to options which may be ordered or retrofitted to the unit. Listed below are the options whichare covered in this section.

1. HOT GAS BYPASS (LOADMINDER) OPTION

2. HIGH AMBIENT OPTION

3. LOCAL PRINTER OPTION

4. OPTIONAL TAMPERPROOF ENCLOSURE (WIRE GRILLE)

5. OPTIONAL DECORATIVE TAMPERPROOF ENCLOSURE (LOUVERED & WIRE GRILLE)

6. OPTIONAL DECORATIVE TAMPERPROOF ENCLOSURE (LOUVERED)

7. OPTIONAL TAMPERPROOF CONDENSER COIL ENCLOSURE (LOUVERED)

8. BAS INTERFACE OPTION (REMOTE RESET OPTION)

the control range and the micro turns the compressoroff. Details for setting the pressure regulator follow.

RWT Control Hot Gas Operation

The hot gas solenoid is energized if the compressor ison its minimum stage of loading and the return watertemperature falls below the following point:

ULCR - CR + CR/20

Where: UCLR = Upper Limit of Control RangeCR = Control Range Differential

Example: In a typical system that requires a 45°F(7.2°C) leaving water temperature, we willhave a 10° (5.6°C) control range (CR) differ-ential which gives us an Upper Limit of Con-trol Range (ULCR) of 55°F (12.8°C). There-fore, plugging the numbers into the formula:

55 - 10 + (10/20) = 45-1/2°F(12.8 - 10 + [10/20] = 7.5°C)

The hot gas solenoid will be activated at 45-1/2°F (7.5°C)in the example above and hot gas may then be fed ac-cording to the suction pressure and the pressure regu-lated valve setting. Once activated, the micro will keepthe solenoid energized until the return water temperaturerises above the temperature designated by the formula:

ULCR - CR + CR/10

Where: UCLR = Upper Limit of Control RangeCR = Control Range Differential

Example: 55 - 10 + 10/10 = 46°F(12.8 - 10 + 10/10 = 7.8°C)

If temperature continues to drop while the Hot Gas isenergized, the Hot Gas will be de-energized when thecompressor cycles off on temperature.

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Procedure For Setting The Hot Gas Regulator(Ref. Fig. 27)

1. If desired, set the control panel data to show suctionpressure.

2. Adjust the pilot power assembly adjustment screw2 to approximately the middle of its adjustmentrange.

3. The chiller must be running and stabilized on theminimum stage capacity. In establishing this condi-tion, it may be necessary to deactivate the regulatorby de-energizing the solenoid 1 .

4. Adjust the adjustment screw 2 in the clockwisedirection to open the valve at a higher pressure(sooner) or in the counterclockwise direction to openthe valve at a lower pressure (slower response). Thevalve is feeding when the valve outlet feels warm tothe touch.

The adjustment is correct when system suction pres-sure rises to a point nearly equal to normal runningpressure at the midpoint in the Control Zone.

5. Further minor adjustment may be necessary to becertain that the valve opens fully before the tempera-ture point at which the compressor stops due to afall in Return or Leaving Water Temp.

6. Repeat this procedure on the other system.

NOTE: Hot gas should not be considered as an addi-tional step of unloading when programming thenumber of steps of loading/unloading.

Field Installation

If it becomes necessary to field install the Hot Gas(Loadminder) Option, kit # 375-21491-000 should be or-dered.

HIGH AMBIENT OPTION

The High Ambient Option consists of two kits, P/Ns 471-01232-131 and 475-19195-000. The option allows opera-tion of the chiller in ambients up to 115°F (46.1°C). Typi-cally, standard operation is limited to 105°F (40.6°C).High ambient operation is accomplished by dischargepressure unloading to assure that the chiller does notfault due to the high pressure cutout opening during hightemperature operation. A sun shield is also installed onthe control panel to prevent direct sunlight from over-heating the control panel causing subsequent malfunc-tion of the electromechanical and electronic componentsin the control panel. Additionally, actual discharge pres-sure readouts can now be obtained from the micro panel.

Discharge Pressure unloading allows the microproces-sor to unload a compressor when the discharge pres-sure approaches a point nearing the discharge pressurecutout. This assures that the system does not shut downcompletely if the cutout were to open. See Page 42 forprogramming the unloading pressure.

Fan cycling by discharge pressure is also available whenthis option is installed (See DISCHARGE PRESSUREREADOUT OPTION this page), however it is of little usein areas where ambients are generally high and stan-dard temperature control of the fans provides good con-trol and maximum efficiency.

LD02099

FIG. 27 PIPING DIAGRAM

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LOCAL PRINTER OPTION

The Micro Panel is capable of supplying a printout ofchiller conditions or fault shutdown information at anygiven time. This allows operator and service personnelto obtain data and system status with the touch of thekeypad. In addition to manual print selection, the micropanel will provide an automatic printout whenever a faultoccurs. An explanation of the keypad use to obtain aprint-out is discussed in the PRINT KEY Section onPage 67.

YORK recommends the field tested WEIGH-TRONIXIMP-24, Model 2600 printer. This is a compact low costprinter that is ideal for service work and data logging.Paper is in the form of a compact roll and is easily handledcompared to larger printers using wider business formstyle paper. The paper is 2.25" (5.7 cm) wide desk-topcalculator paper that can be easily and inexpensivelypurchased at most stationery stores. Shown in Fig. 28and 29 is the WEIGH-TRONIX printer and a typical sampleprintout.

The WEIGH-TRONIX IMP-24 Model 2600 printer can bepurchased for approximately $150.00. Contact Weigh-Tronix for purchase information:

Weigh-Tronix2320 Airport Blvd.Santa Rosa, CA 95402Phone: 1-800-358-9110 or 1-707-527-5555

(International Orders Only)

NOTE: The print-out is made to be universal to all typesof chillers both air and water cooled with or with-out options. Items may be indicated on the print-out which may not be present on the chiller.

Installation Limitations

The following limitations must be adhered to. Failure todo so may result in improper printer and/or chiller opera-tion.

1. The printer option is adaptable to all versions andrevisions of Microprocessor boards and EPROMs.No modifications are necessary to the panel.

2. Maximum cable length between the printer and theMicroprocessor Board is 25 feet (7.6 m). Twistedpair shielded cable is required.

3. The printer must be supplied a 115VAC source.

4. The printer may be left connected to the micro panel.

FIG. 29 PRINTOUT

YORK INTERNATIONAL CORPORATIONRECIPROCATING WATER CHILLERS

SYSTEM STATUS8:45AM 4/17/98

SYS 1 COMPRESSOR RUNNINGSYS 2 ANTI-COIN TIMER 13 SEC

RETURN WATER TEMP 65.0 DEGFLEAVING WATER TEMP 54.0 DEGFLOW WATER CUTOUT 36.0 DEGFSETPOINT TEMP 45.0 DEGFOUTSIDE AIR TEMP 75.0 DEGFLOW AMBIENT CUTOUT 10.0 DEGFLOW PRESSURE CUTOUT 4 4 PSIGLEAD SYSTEM SYS 1CONTROL TYPE LCHWTCOOLING RANGE 45.0 TO 47.0 DEGF

SYSTEM 1 DATA

COMPRESSOR STATUS ONMOTOR AMPS 5 0 %FLASUCTION PRESSURE 6 1 PSIGDISCHARGE PRESSURE 143 PSIGOIL PRESSURE 7 5 PSIDLIQUID LINE SOLENOID OFFRUN PERMISSIVE ONSTAGES OF LOADING 1FORWARD FANS OFFREVERSE FANS OFFHOT GAS BYPASS VALVE OFF

SYSTEM 2 DATA

COMPRESSOR STATUS ONMOTOR AMPS 0 %FLASUCTION PRESSURE 6 1 PSIGDISCHARGE PRESSURE 8 0 PSIGOIL PRESSURE 1 PSIDLIQUID LINE SOLENOID OFFRUN PERMISSIVE ONSTAGES OF LOADING 1FORWARD FANS 1REVERSE FANS OFFHOT GAS BYPASS VALVE OFF

S M T W T F S *=HOLIDAYSUN START=06:00AM STOP=11:00AMMON START=06:00AM STOP=11:00AMTUE START=06:00AM STOP=11:00AMWED START=06:00AM STOP=11:00AMTHU START=06:00AM STOP=11:00AMFRI START=06:00AM STOP=11:00AMSAT START=06:00AM STOP=11:00AMHOL START=00:00AM STOP=00:00AM

FIG. 28 WEIGH-TRONIX IMP-24 MODEL 2600 PRINTER

23889A

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Parts

The following parts are required:

1. Weigh-Tronix IMP-24, Model 2600 printer.

2. 2.25" (5.7 cm) wide desk top calculator paper.

3. 25 ft. (7.62 m) Twisted Pair Shielded Cable (mini-mum 3 conductor), # 18 AWG Stranded, 300V min.insulation.

4. (1 ea.) 25pin Cannon connector and shell. Connec-tor: Cannon P/N DB-25P or equivalent. Shell: Can-non P/N DB-C2-J9.

Assembly and Wiring

All components should be assembled and wired as fol-lows in Fig. 30. Strip the outside insulation back severalinches and individual wires about 3/8" (9.5 mm) to con-nect the cable at the Micro Logic Board. Connect theshield of the cable as shown on the Micro Logic Board.Do not connect at the printer end of the cable.

Printer Configuration

2 Switches on the printer must be properly configured.Remove the paper roll to access these switches. Placethe switches in the following positions:

SW. 1 OFFSW. 2 ON

Obtaining a Printout

A printout of current operating data may be obtained bypressing the OPER DATA key. A snapshot will be taken

by the micro of current operating conditions. These con-ditions will be stored in memory until they can be trans-mitted to the printer and printed. A sample printout isshown in Fig. 19 on page 63.

A printout of the fault shutdown history may be obtainedby pressing the HISTORY key. A printout showing thelast 3 faults with all system conditions at the time of thefault will be transmitted. A sample printout is shown inFig. 20 on page 64.

An automatic printout will be sent to the printer when-ever the chiller shuts down on a fault, regardless ofwhether the fault causes a system or the entire chiller tolockout or whether restart is permitted. This is the sameprintout that is obtained when the OPER DATA Key ispressed, however it will be a snapshot of system operat-ing conditions at the instant fault occurred. Additionally,the Status indication that is noted in the printout willnote the specific fault that occurred.

Using Other Printers

Control codes vary from printer to printer. This will resultin unusual formatting of printed data from many printers.In addition, handshaking lines and handshaking se-quence will differ between printers. This makes the equip-ment susceptible to operation problems or mis-wiringwhich may cause damage to the printer or the Micropro-cessor Board. YORK assumes no responsibility for as-sistance or damage in the use of non-specified printers.

Warranty

YORK assumes no warranty responsibility in the use ofthe printer. This includes damages to the printer and theMicroprocessor Boards or chiller operation problemswhich may result.

LD02100

FIG. 30 ASSEMBLY AND WIRING

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FIG. 31 COMPLETE GRILLE INSTALLATION(Different unit shown)

27577A

OPTIONAL TAMPEPROOF ENCLOSURE(WIRE GRILLE)

General

A wire grille tamperproof enclosure is available for thechiller for the prime purpose of deterring unauthorizedaccess to components on the chiller.

Kit 475-21467-000 is the tamperproof enclosure whichconsists of weather resistant steel grilles as well as thenecessary mounting hardware.

Installation

1. Refer to Fig. 31 and the associated parts list. Beforestarting installation, all of the items in the kit shouldbe identified by comparing with Fig. 32 and the as-sociated parts list.

2. All holes for mounting kit parts are provided in boththe chiller frame and the added supports, therefore,it should be unnecessary to drill holes.

3. Install grilles using the proper hardware and sup-ports. Refer to Fig. 32 and the Parts List for place-ment of the grilles and the proper hardware required.

4. Notch grilles to suit water connection and wiringharnesses as needed.

5. If the High Ambient Sunshield Kit or DisconnectOption is installed, field adaptation will be requiredwhere parts of the kits interfere. Touch up exposedmetal parts to prevent rust.

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NOTES:

1. Notch grilles to suit water connections and wiring harnesses.

2. Discard hardware kit items 56, 59, and 60.

LD02700

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91YORK INTERNATIONAL

OPTIONAL DECORATIVE TAMPEPROOF ENCLOSURE(LOUVERED & WIRE GRILLE)

General

A combination louvered and wire grille enclosure is avail-able for the chiller for the prime purpose of deterring un-authorized access to components of the chiller.

Kit 475-21466-000 is a decorative/tamperproof enclosurewhich consists of a combination of louvered sheet metalpanels and weather resistant wire grilles along with mount-ing hardware. This kit has a further purpose of present-ing a pleasing appearance to the chiller when it is lo-cated in a highly visible area.

Installation

1. Before starting installation, all of the items in the kitshould be identified by comparing with Fig. 33A and33B and the associated parts lists.

2. All holes for mounting kit parts are provided in boththe chiller frame and the added supports, therefore,it should be unnecessary to drill holes.

3. Install the louvered panels and wire grilles using theproper hardware and supports. Refer to Fig. 37a,37b, 37c and the Parts List for placement of thegrilles/panels and the proper hardware required. Dis-card existing grilles to attach the louvered panelswhere necessary.

4. Notch grilles to suit water connection and wiringharnesses as needed.

5. If the High Ambient Sunshield Kit or DisconnectOption is installed, field adaptation will be requiredwhere parts of the kits interfere. Touch up exposedmetal parts to prevent rust.

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LD02701NOTES:

1. Discard hardware kit items 55 - 57, 59 - 61, and 63.

2. Notch grilles to suit water connections and wiring harnesses.

3. Discard existing grilles to attach louver panels where necessary.

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LD02702

FIG. 33B GRILLE AND LOUVER INSTALLATION (FRONT AND BACK)

NOTES:

1. Discard hardware kit items 55 - 57, 59 - 61, and 63.

2. Notch grilles to suit water connections and wiring harnesses.

3. Discard existing grilles to attach louver panels where necessary.

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FIG. 34 COMPLETE LOUVER INSTALLATION(Different unit shown)

28364A

OPTIONAL DECORATIVE TAMPERPROOF ENCLOSURE(LOUVERED)

General

A louvered tamperproof enclosure is available for thechiller for the prime purpose of deterring unauthorizedaccess to components of the chiller.

Kit 475-02834-000 is the decorative/tamperproof enclo-sure which consists entirely of louvered sheet metal pan-els along with mounting hardware. This kit has a furtherpurpose of presenting a pleasing appearance to the chillerwhen it is located in a highly visible area.

Installation

1. Refer to Fig. 34 for a photo of the completed instal-lation. Before starting installation, all of the items inthe kit should be identified by comparing with Figs.35A, 35B and the associated parts lists.

2. All holes for mounting kit parts are provided in boththe chiller frame and the added supports, therefore,it should be unnecessary to drill holes.

3. Install the louvered panels using the proper hard-ware and supports. Refer to Fig. 35A, 35B and theParts List for placement of the panels and the properhardware required. Discard existing grilles to attachthe louvered panels where necessary.

4. Notch panels to suit water connections and wiringharnesses as needed.

5. If the High Ambient Sunshield Kit or DisconnectOption is installed, field adaptation will be requiredwhere parts of the kits interfere. Touch up exposedmetal parts to prevent rust.

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LD02703

FIG. 35A LOUVER INSTALLATION (SIDES)

NOTES:

1. For standard units (withcooler) discard items9007, 9008, and neces-sary hardware.

2. Discard hardware kititems 55 - 63.

3. For single point wiringoption, discard items9007, 9010, 9016, andnecessary hardware.

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LD02704

FIG. 33B GRILLE AND LOUVER INSTALLATION (FRONT AND BACK)

NOTES:

1. For standard units (with cooler) discard items 9007, 9008, and neces-sary hardware.

2. Discard hardware kit items 55 - 63.

3. For single point wiring option, discard items 9007, 9010, 9016, andnecessary hardware.

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OPTIONAL TAMPERPROOF CONDENSERCOIL ENCLOSURE (LOUVERED)

General

A condenser coil tamperproof enclosure is available forthe chiller for the prime purpose of protecting the con-denser coils.

Kit 475-23840-000 is the tamperproof enclosure whichconsists of louvered sheet metal as well as the neces-sary mounting hardware.

Installation

1. Before starting installation, all of the items in the kitshould be identified by comparing with Fig. 36A, 36Band the associated parts list.

2. All holes for mounting kit parts are provided in boththe chiller frame and the added supports; therefore,it should be unnecessary to drill holes.

3. Install louvered panels using the proper hardware andsupports. Refer to Fig. 36A and 36B and the PartsList for placement of the panels and the proper hard-ware required.

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LD02705NOTES:

1. Discard existing grilles to attach louver panels where necessary.

2. Discard items 51 - 53, and 55 - 63 from hardware kit.

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FIG. 36B CONDENSER COIL LOUVER INSTALLATION (BACK)

LD02706

NOTES:

1. Discard existing grilles to attach louver panels where necessary.

2. Discard items 51 - 53, and 55 - 63 from hardware kit.

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REMOTE RESET OPTION

The Remote Reset Option allows resetting of the watertemperature setpoint using a 0 - 10VDC input, a 4 - 20mAinput, or a dry contact. The electronic circuitry in theoption converts the signals mentioned above into pulsewidth modulated (PWM) signals which the microproces-sor can understand. Whenever an offset is called for, thechange may be noted by the user by pressing the RE-MOTE RESET TEMP/RANGE Key on the Keypad. Allrefresh requirements normally associated with PWM in-puts will be automatically taken care of by the electron-ics in the option.

It is important to note that the maximum offset, whenthis option is installed, is 20°F (11.1°C). This is due tothe electronics limitation of maximum 11 sec. pulse. Ifan offset greater than 20°F (11.1°C) is required, a usersupplied PWM signal of up to 21 sec. is needed and theRemote Reset Option cannot be installed.

The Remote Reset Option P/N 471-01232-181 consistsof a Remote Reset printed circuit board, a mountingbracket and associated wiring. Each of the 3 signal typeswill require individual jumpering of the printed circuit board.This will be discussed in the following text.

0 - 10VDC

Jumpers JU2 and JU4 must be IN. All other jumpersshould be OUT. Program the REMOTE TEMP SETPOINTRANGE (page 72) for 40°F (4.4°C) which will allow a20°F (11.1°C) offset with an input of 10VDC. The tem-perature will be offset linearly according to the voltage (0- 10VDC) applied.

The 0 - 10VDC signal should be connected to the + and- terminals on the TB3 Terminal Block at the right of theMicroprocessor Board. Be sure polarity is correct.

CAUTION: THE 0 - 10VDC INPUT SIGNAL WIRINGMUST NOT BE EARTH GROUNDED!

4 - 20mA

Jumpers JU3 and JU5 must be IN. All other jumpersshould be OUT. Program the REMOTE TEMP SETPOINTRANGE (page 72) for 40°F (4.4°C) which will allow a20°F (11.1°C) offset with an input of 20mA. There will beno offset with an input of 4mA. The temperature will beoffset linearly according to the current (4 - 20mA) ap-plied.

The 4 - 20mA input signal should be connected to the +and - terminals on the TB3 Terminal Block at the rightof the Microprocessor Board. Be sure polarity is correct.

CAUTION: THE 4 - 20mA INPUT SIGNAL WIRINGMUST NOT BE EARTH GROUNDED!

Dry Contact

A dry contact may also be used to offset temperature.This allows a single offset whenever the contact is closed.The offset is determined by the adjustment of the R11potentiometer on the Remote Reset Board. Adjust thepotentiometer as needed to obtain the desired offset.

Jumper JU1 must be IN. All other jumpers must be OUT.Program the REMOTE RESET TEMP SETPOINTRANGE (page 72) for 40°F (4.4°C) which will allow theR11 pot to be adjusted for an offset of as much as 20°F(11.1°C) when the contact is closed.

The dry contact should be connected directly to the P1-1 (J1-1) and P1-2 (J1-2) terminals on the Remote ResetBoard (Fig. 41).

NOTE: The coil of the controls used for reset must besuppressed. Use YORK P/N 031-00808-000 sup-pressor.

The Remote Setpoint Reset will not operatewhen a Remote Control Center Option is con-nected to the Micropanel. The Remote Con-trol Center will always determine the setpoint.

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FIG. 37 REMOTE RESET BOARD

LD02707

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No display on panel 1. No 115VAC to 2T. 1. Checking wiring and fuses (1 FU and 2Unit will not operate FU). Check emergency stop contacts

5 to 1 .

2. No 24VAC to Power Supply Board. 2. Check wiring 2T to Power Supply Board.3. 2T defective, no 24VAC output. 3. Replace 2T.4. No +12V output from Power Supply 4. Replace Power Supply Board or isolate

Board excessive load on the board.Contact YORK Service Before Replacing Circuit Boards!

NO RUN PERM 1. No Flow 1. Check chilled liquid flow.2. Flow switch installed improperly. 2. Check that flow switch is installed

according to manufacturers instructions.3. Defective flow switch. 3. Replace flow switch.4. Remote cycling device open. 4. Check cycling devices connected to

terminals 13 & 14 of the TB3 TerminalBlock.

5. System switch in the OFF position 5. Place switches to the ON position.

MOTOR CURRENT CONTACTOR DOES NOT ENERGIZEFAULT 1. External high pressure 1. Check external high pressure switch, fan

switch tripped. operation, and discharge pressure storedin memory. Air flow from fans must be up.

2. External motor protector tripped. 2. Check for defective External motorprotector, wiring and motor problems. As-sure that motor protector is not tripped due

Motor contactor may to external high pressure switch.or may not energize 3. Defective relay output board. 3. Replace relay output board.

CONTACTOR ENERGIZES1. Improper system high voltage. 1. Check system high voltage supply.2. Defective contactor contacts 2. Check contacts and contactors.

and contactor.3. Faulty high voltage wiring. 3. Check wiring.4. High motor current stored in memory. 4. Loose calibration resistors in J9 (SYS 1)

or J10 (SYS 2) of power supply board.5. Defective current transformer (CT). 5. CT resistance 42-44Ω.

Contact YORK Service Before Replacing Circuit Boards or C.T.s!

LOW OIL PRESS 1. Low oil charge. 1. Oil level should be visible in either sightFAULT glass at all times. Add YORK C oil if

necessary.2. Too much refrigerant-in oil, partic- 2. Check crankcase oil heater operation.

ularly on start-up. (350 Watt heater should be ON whenunit is OFF. Measure heater current.(Should be min. 2 amps.)

3. Liquid Line Solenoid Valve (LLSV) 3. Check wiring and LLSV.not operating.

4. Suction Press. Transducer or wiring 4. Compare display to a gauge (SYS OFF).defective. Replace defective component.

5. Oil Press. Transducer or wiring 5. Compare suction and oil gauges to display.defective. Replace defective component.

TROUBLESHOOTING CHART

PROBLEM CAUSE SOLUTION

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Low Suction Fault 1. Improper Suction Pressure Cut-out 1. Adjust per recommended settings andadjustment. restart unit.

2. Low refrig. charge. 2. Repair leak / add refrigerant.3. Fouled filter drier. 3. Change drier core.4. Thermal expansion valve adjust- 4. Adjust compressor suction superheat to

ment / failure. 11°F (6.1°C) or replace power element(or valve).

5. Reduced flow of chilled liquid 5. Check GPM (See OPERATING LIMIT-through cooler. ATIONS) Check operation of pump.

Clean pump strainer, purge chilled liquidsystem of air.

6. Defective suction press. transducer. 6. Replace transducer.7. Fouled compressor suction strainer. 7. Remove and clean strainer.8. Faulty wiring to transducer. 8. Check wiring.

High Dsch Fault 1. Condenser fans not operating or 1. Check fans, fuses, and contactors.Cuts out on High Dis- rotating backwards.charge Pressure as 2. Too much refrigerant. 2. Remove refrigerant.sensed by Micropro- 3. Air in Refrigerant System. 3. Evacuate and recharge.cessor via high dis- 4. Defective discharge pressure 4. Replace discharge pressure transducer.charge pressure transducer.transducer. 5. Assure Programmable H.P. Cut-out 5. Adjust per recommended settings and

is correctly set. restart unit.NOTE: If external H.P. 6. Assure OAT sensor is reading 6. Place a thermometer next to the sensorCut-out Switch opens, properly. and compare reading to the display. Op-a Motor Current Fault eration should not suffer if thermometerwill result. is +/ 10°F (5.6°C).

Chiller Fault: High 1. Temperature sensed incorrectly 1. Verify actual ambient temperature at probeAmbient Temp by thermistor. +/ 10°F (5.6°C) with a thermometer placedCuts out on high ambi- next to the OAT sensor.ent temperature. 2. Fans rotating backwards. 2. Air flow must be up. Correct fan rotation.(Max. = 130°F (54.4°C) 3. Air flow to unit restricted (or being 3. Check installation clearances.will restart automatically re-circulated). (See pages 10 and 11).if temperature drops 4. High ambient cut-out set too low. 4. Reprogram cut-out.below 128°F [53.3°C]).

Chiller Fault: Low 1. Temperature of outside air is below 1. No problem exists.Ambient Temp cut-out setting.Cuts out on low 2. Temperature sensed incorrectly by 2. Verify actual ambient temperature imme-ambient temperature. thermistor. diately at probe with thermometer.(25°F [-3.9°C] min. for 3. Check low ambient temperature 3. Adjust if necessary.std. adjustable for low Cut-out setting on the display. NOTE: For occasional operation belowambient unit) 0°F (-17.8°C) , set the cut-out at 0°FNOTE: Operation below (-17.8°C) chiler is then allowed to operate25°F (-3.9°C) requires regardless of temperature. A low ambientlow ambient accessory. kit must be installed.

Chiller Fault: Low 1. RWT Control ONLY: Control range 1. Flow is lower than design. Increase flow orWater Temp is too small and does not match increase the control range to match actual

actual ∆T across evaporator under evaporator ∆T.Low water temperature full load conditions.shutdown 2. Check LWT cut-out point on panel. 2. Adjust if necessary, and restart unit.

(See page 45).

PROBLEM CAUSE SOLUTION

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Chiller Fault: Low 3. Defective LWT or RWT sensor. 3. Check according to following table (useWater Temp (Assure the sensor is properly in- digital volt meter)*. Replace if necessary.(Contd) stalled in the bottom of the well

with a generous amount of heat TEMP. VOLTAGE (DC)conductive compound. 20.0°F 1.65NOTE: It is not unusual to find up 22.0°F 1.71to a +/2°F difference between the 25.0°F 1.82display and a thermometer located 27.0°F 1.88in water piping. 30.0°F 1.99

33.0°F 2.0936.0°F 2.2238.0°F 2.2841.0°F 2.3743.0°F 2.4346.0°F 2.5448.0°F 2.6050.0°F 2.6753.0°F 2.7755.0°F 2.8357.0°F 2.8959.0°F 2.9561.0°F 3.0263.0°F 3.0865.0°F 3.1467.0°F 3.2070.0°F 3.28

* Check voltage on Microprocessor Board.LWT: J11-7 to J11-1RWT: J11-8 to J11-1

Low Compressor Oil 1. Low oil charge. 1. Oil level should be visible in either sightLevel glass at all times. Add YORK C oil if(Particularly at necessary.start-up) 2. Excessive flood back of liquid 2. Adjust Thermal Expansion Valve (TXV) or

refrigerant. replace power element. Check TXV bulblocation. Should be located on suction lineat least 8" - 10" from nearest elbow. Bulbshould be at 4 oclock or 8 oclock position,have good contact with suction line and bewell insulated.

Crankcase Heater 1. Open at 115VAC wiring to heater. 1. Check wiring.wont Energize 2. Defective heater. 2. Replace heater.(Should energize any- 3. Auxiliary contacts of compressor 3. Replace contactor.time unit is OFF) contactor defective.(Min. current draw = 2amps)

Compressor wont 1. Suction pressure > programmed un- 1. Excessive load. Check OPERATING LIMI-load load point or operating limitations TATIONS. Check programmed unloading(Solenoid valve de- have been exceeded. point.energizes to load 2. Discharge pressure > programmed 2. Check OPERATING LIMITATIONS.compressor) unload point or operating limitations Check programmed unloading point.

have been exceeded.3. Demand not great enough. 3. OK. Become familiar with control operation.4. Defective loading solenoid. 4. Replace compressor loading solenoid.

PROBLEM CAUSE SOLUTION

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Compressor wont 5. Faulty wiring to loading solenoid. 5. Check wiring.load 6. Defective water temperature sensor. 6. Compare sensor with a thermometer. Var-(Contd) iation of sensor vs. thermometer of +/2°F

is not unusual. Replace if necessary.7. Defective evaporator or optional 7. Replace transducer after verifying with a

discharge transducer. gauge.

Lack of Cooling 1. Fouled evaporator surface. 1. Contact the local YORK service represen-Effect tative.

2. Faulty compressor suction and / or 2. Contact the local YORK service represen-charge valves. tative.

PROBLEM CAUSE SOLUTION

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TEMPERATURE CONVERSION TABLES

The numbers in bold-face type in the center column refer to the temperature, either in Centigrade or Fahrenheit, which is tobe converted to the other scale. Converting Fahrenheit to Centigrade the equivalent temperature will be found in the leftcolumn. If converting Centigrade to Fahrenheit, the equivalent temperature will be found in the column on the right.

TEMPERATURE°C °C or °F °F

+60.0 +140 +284.0+60.6 +141 +285.8+61.1 +142 +287.6+61.7 +143 +289.4+62.2 +144 +291.2+62.8 +145 +293.0+63.3 +146 +294.8+63.9 +147 +296.6+64.4 +148 +298.4+65.0 +149 +300.2+65.6 +150 +302.0+66.1 +151 +303.8+66.7 +152 +305.6+67.2 +153 +307.4+67.8 +154 +309.2+68.3 +155 +311.0+68.9 +156 +312.8+69.4 +157 +314.6+70.0 +158 +316.4+70.6 +159 +318.2+71.1 +160 +320.0+71.7 +161 +321.8+72.2 +162 +323.6+72.8 +163 +325.4+73.3 +164 +327.2+73.9 +165 +329.0+74.4 +166 +330.8+75.0 +167 +332.6+75.6 +168 +334.4+76.1 +169 +336.2+76.7 +170 +338.0+77.2 +171 +339.8+77.8 +172 +341.6+78.3 +173 +343.4+78.9 +174 +345.2+79.4 +175 +347.0+80.0 +176 +348.8+80.6 +177 +350.6+81.1 +178 +352.4+81.7 +179 +354.2+82.2 +180 +356.0+82.8 +181 +357.8+83.3 +182 +359.6+83.9 +183 +361.4+84.4 +184 +363.2+85.0 +185 +365.0+85.6 +186 +366.8+86.1 +187 +368.6+86.7 +188 +370.4+87.2 +189 +372.2+87.8 +190 +374.0+88.3 +191 +375.8+88.9 +192 +377.6+89.4 +193 +379.4+90.0 +194 +381.2+90.6 +195 +383.0+91.1 +196 +384.8+91.7 +197 +386.6+92.2 +198 +388.4+92.8 +199 +390.2

TEMPERATURE°C °C or °F °F

+26.7 +80 +176.0+27.2 +81 +177.8+27.8 +82 +179.6+28.3 +83 +181.4+28.9 +84 +183.2+29.4 +85 +185.0+30.0 +86 +186.8+30.6 +87 +188.6+31.1 +88 +190.4+31.7 +89 +192.2+32.2 +90 +194.0+32.8 +91 +195.8+33.3 +92 +197.6+33.9 +93 +199.4+34.4 +94 +201.2+35.0 +95 +203.0+35.6 +96 +204.8+36.1 +97 +206.6+36.7 +98 +208.4+37.2 +99 +210.2+37.8 +100 +212.0+38.3 +101 +213.8+38.9 +102 +215.6+39.4 +103 +217.4+40.0 +104 +219.2+40.6 +105 +221.0+41.1 +106 +222.8+41.7 +107 +224.6+42.2 +108 +226.4+42.8 +109 +228.2+43.3 +110 +230.0+43.9 +111 +231.8+44.4 +112 +233.6+45.0 +113 +235.4+45.6 +114 +237.2+46.1 +115 +239.0+46.7 +116 +240.8+47.2 +117 +242.6+47.8 +118 +244.4+48.3 +119 +246.2+48.9 +120 +248.0+49.4 +121 +249.8+50.0 +122 +251.6+50.6 +123 +253.4+51.1 +124 +255.2+51.7 +125 +257.0+52.2 +126 +258.8+52.8 +127 +260.6+53.3 +128 +262.4+53.9 +129 +264.2+54.4 +130 +266.0+55.0 +131 +267.8+55.6 +132 +269.6+56.1 +133 +271.4+56.7 +134 +273.2+57.2 +135 +275.0+57.8 +136 +276.8+58.3 +137 +278.6+58.9 +138 +280.4+59.4 +139 +282.2

TEMPERATURE°C °C or °F °F-6.7 +20 +68.0-6.1 +21 +69.8-5.5 +22 +71.6-5.0 +23 +73.4-4.4 +24 +75.2-3.9 +25 +77.0-3.3 +26 +78.8-2.8 +27 +80.6-2.2 +28 +82.4-1.7 +29 +84.2-1.1 +30 +86.0-0.6 +31 +87.80.0 +32 +89.6+.6 +33 +91.4

+1.1 +34 +93.2+1.7 +35 +95.0+2.2 +36 +96.8+2.8 +37 +98.6+3.3 +38 +100.4+3.9 +39 +102.2+4.4 +40 +104.0+5.0 +41 +105.8+5.5 +42 +107.6+6.1 +43 +109.4+6.7 +44 +111.2+7.2 +45 +113.0+7.8 +46 +114.8+8.3 +47 +116.6+8.9 +48 +118.4+9.4 +49 +120.2

+10.0 +50 +122.0+10.6 +51 +123.8+11.1 +52 +125.6+11.7 +53 +127.4+12.2 +54 +129.2+12.8 +55 +131.0+13.3 +56 +132.8+13.9 +57 +134.6+14.4 +58 +136.4+15.0 +59 +138.2+15.6 +60 +140.0+16.1 +61 +141.8+16.7 +62 +143.6+17.2 +63 +145.4+17.8 +64 +147.2+18.3 +65 +149.0+18.9 +66 +150.8+19.4 +67 +152.6+20.0 +68 +154.4+20.6 +69 +156.2+21.1 +70 +158.0+21.7 +71 +159.8+22.2 +72 +161.6+22.8 +73 +163.4+23.3 +74 +165.2+23.9 +75 +167.0+24.4 +76 +168.8+25.0 +77 +170.6+25.6 +78 +172.4+26.1 +79 +174.2

TEMPERATURE°C °C or °F °F

-40.0 -40 -40.0-39.4 -39 -38.2-38.9 -38 -36.4-38.3 -37 -34.6-37.8 -36 -32.8-37.2 -35 -31.0-36.7 -34 -29.2-36.1 -33 -27.4-35.6 -32 -25.6-35.0 -31 -23.8-34.4 -30 -22.0-33.9 -29 -20.2-33.3 -28 -18.4-32.8 -27 -16.6-32.2 -26 -14.8-31.7 -25 -13.0-31.1 -24 -11.2-30.6 -23 -9.4-30.0 -22 -7.6-29.4 -21 -5.8-28.9 -20 -4.0-28.3 -19 -2.2-27.8 -18 -0.4-27.2 -17 +1.4-26.7 -16 +3.2-26.1 -15 +5.0-25.6 -14 +6.8-25.0 -13 +8.6-24.4 -12 +10.4-23.9 -11 +12.2-23.3 -10 +14.0-22.8 -9 +15.8-22.2 -8 +17.6-21.7 -7 +19.4-21.1 -6 +21.2-20.6 -5 +23.0-20.0 -4 +24.8-19.4 -3 +26.6-18.9 -2 +28.4-18.3 -1 +30.2-17.8 0 +32.0-17.2 +1 +33.8-16.7 +2 +35.6-16.1 +3 +37.4-15.6 +4 +39.2-15.0 +5 +41.0-14.4 +6 +42.8-13.9 +7 +44.6-13.3 +8 +46.4-12.8 +9 +48.2-12.2 +10 +50.0-11.7 +11 +51.8-11.1 +12 +53.6-10.6 +13 +55.4-10.0 +14 +57.2

-9.4 +15 +59.0-8.9 +16 +60.8-8.3 +17 +62.6-7.8 +18 +64.4-7.2 +19 +66.2

Page 107: Millennium LIQUID CHILLERS AIR-COOLED – …

FORM 150.60-NM5

107YORK INTERNATIONAL

Page 108: Millennium LIQUID CHILLERS AIR-COOLED – …

Proud Sponsorof the 1998U.S. Olympic Team

36USC380

P.O.Box1592,York, PennsylvaniaUSA 17405-1592 Subject to changewithout notice. Printed inUSA

Copyright©byYork International Corporation 1998 ALLRIGHTSRESERVED

Form 150.60-NM5 (298)

Supersedes: 150.60-NM3 inERRonly.