Installation, Operation and Maintenance Manual IOMM A-C Cond

Group: Chiller Part Number: 331376901 Effective: March 2007 Supersedes: IMM ACAQ-1

Air-Cooled Condensers

Model ACH 014 - 225 Model ACX 014 - 225 Model ACL 014 - 225 Capacities from 130 MBH to 2225 MBH R-22, R-134a

Table of Contents

Introduction........................................................................................................................3

Installation..........................................................................................................................3 Handling ....................................................................................................................................................3 Holding Charge..........................................................................................................................................4 Unit Location .............................................................................................................................................4 Sound/Vibration.........................................................................................................................................4 Rigging ......................................................................................................................................................5 Walls or Obstructions.................................................................................................................................5 Multiple Units ............................................................................................................................................6 Units in Pits................................................................................................................................................6 Decorative Fences......................................................................................................................................6

Dimensions..........................................................................................................................7

Refrigerant Piping .............................................................................................................8 Refrigerant Piping......................................................................................................................................8 Valves.........................................................................................................................................................8 Discharge Lines .........................................................................................................................................9 R-410A ......................................................................................................................................................9

Physical Data ....................................................................................................................10

Electrical Data..................................................................................................................11

Operation..........................................................................................................................18 Start-Up....................................................................................................................................................18 Discharge Gas Pulsation ..........................................................................................................................18 Discharge Pressure Control .....................................................................................................................18 Fan/Circuit Configuration........................................................................................................................19 Control options: .......................................................................................................................................19

Maintenance .....................................................................................................................26 Cleaning Instructions ...............................................................................................................................26

Manufactured in an ISO certified facility

©2007 McQuay International Illustrations cover the general appearance of McQuay International products at the time of publication and we reserve the right

to make changes in design and construction at anytime without notice.

2 IOMM A-C Cond

MODEL CODE AC H 100 A S

Introduction Carefully check each shipment against the bill of lading and account for all items. Report any shortage or damage to the delivering carrier.

On receipt of equipment, check the unit nameplate for correct electrical characteristics and working pressure. Refrigerants R-22, R-134a, R-407c have 450 psi; R-410a has 650 psi.

Be careful to prevent damage when uncrating. Heavy equipment should be left on unit’s shipping base until it has been moved to the final location.

This equipment must be installed in accordance with accepted industry standards. Failure to meet the following conditions may void the warranty:

1. System piping must be installed following industry standards for good piping practices. 2. Inert gas must be charged into piping during brazing/welding. 3. System must be thoroughly leak-checked and evacuated before initial charging. High

vacuum gauge capable of reading microns is mandatory. Dial indicating pressure gauges are not acceptable.

4. Power supply to system must meet the following conditions:

Voltage for 208/230 motors not less than 195 volts or more than 253 volts. All other voltages must be within 10% of nameplate ratings. Phase imbalance not to exceed 2%.

5. All controls and safety switch circuits properly connected per wiring diagram. 6. Factory installed wiring must not be changed without written factory approval. 7. Relief valves must meet all code requirements.

Installation

Handling Note: Installation and maintenance are to be performed only by qualified personnel who are familiar with local codes and regulations, and experienced with this type of equipment.

Avoid rough handling shock due to impact or dropping the unit. Do not push or pull unit.

Never allow any part of the unit to fall during unloading or moving, as this can result in serious damage.

! DANGER

Dangers indicate a hazardous situation which will result in death or serious injury if not avoided.

Improper lifting or moving of unit can result in property damage, severe personal injury or death. Follow rigging and moving instructions carefully.

Fan Rows/Circuits Air-cooled Condenser S=Single, D=Dual

Series: H, L, X Nominal Evaporator Tons Vintage

IOMM A-C Cond 3

Holding Charge The unit is shipped with a holding charge of dry nitrogen under nominal pressure.

Unit Location Units are designed for outdoor application and may be mounted on a roof or concrete slab (ground level installation). Install roof-mounted units on steel channels or an I-beam frame to support the unit above the roof. Use of vibration pads or isolators is recommended. The roof must be strong enough to support the operating weight of the unit.

For ground level installation, mount units on a one-piece concrete slab with footings extending below the frost line. Be certain concrete slabs are installed level and are properly supported to prevent settling.

Locate the condenser far enough away from any wall or other obstruction to provide sufficient clearance for air entrance. Do not attach ductwork to the coil inlet or fan outlet. Avoid air recirculation conditions that may be caused by sight screening, walls, etc. and keep unit fan discharge away from any building air intakes. Do not install unit where exhaust or ventilation equipment will affect entering air temperature or foul coils.

! WARNING

Warnings indicate potentially hazardous situations, which can result in property damage, severe personal injury, or death if not avoided.

This equipment may contain a substance which harms the public health and environment by destroying ozone in the upper atmosphere. Venting of

certain refrigerants to the atmosphere is illegal. Refrigerant recovery devices must be used when installing or servicing this product.

Sound/Vibration Install units away from occupied spaces, utility areas, corridors and auxiliary spaces to reduce the transmission of sound and vibration to occupied spaces. The refrigerant piping should be flexible enough to prevent the transmission of noise and vibration from the unit into the building. If the refrigerant lines are to be suspended from the structure of the building, use isolation hangers to prevent the transmission of vibration. Where piping passes through a wall, pack fiberglass and sealing compound around the lines to minimize vibration and retain flexibility. The unit must be secured in its final location. Holes are provided in the base runner for this purpose.

4 IOMM A-C Cond

Rigging Figure 1, Unit Rigging

Walls or Obstructions Locate the unit to ensure air can circulate freely and not be recirculated. For proper air flow and access, maintain the minimum distance from the unit to the wall as shown to the right. Increase this distance whenever possible. Leave maintenance room through access doors and panels. Overhead obstructions are not permitted. When enclosed by three walls, install unit as indicated for units in a pit.

ACH = 4 ft.ACL/ACX = 6 ft.

AIR FLOW

IOMM A-C Cond 5

Multiple Units

ACH = 6 ft.ACL/ACX = 8 ft.

AIR FLOW AIR FLOWFor units placed side by side, the minimum distance between units must be as shown to the right. If units are placed end to end, the minimum distance between units is 4 feet.

Units in Pits The top of the unit should not be more than two feet below top of the pit, and side distance should be as shown. If the top of the unit is not level with the top of pit, discharge cones or stacks must be used to raise discharge air to the top of the pit. This is a minimum requirement.

ACH = 4 ft.

ACL/ACX = 6 ft.

STACK(BY OTHERSIF SUPPLIED) 2 FT. MAX.

AIR FLOW

ACH = 4 ft.ACL/ACX = 6 ft.

Decorative Fences Fences must have 50% free area, with 1 foot undercut, at least the width of condenser minimum clearance, and must not exceed the top of unit. If these requirements are not met, unit must be installed as indicated for "Units in pits".

ACH = 3 ft.

ACL/ACX = 4 ft.

1 IN.MIN.

AIR FLOW

ACH = 3 ft

ACL/ACX = 4 ft.

6 IOMM A-C Cond

Dimensions

Note: All dimensions in inches unless otherwise indicated

IOMM A-C Cond 7

Refrigerant Piping Figure 2 illustrates a typical piping arrangement involving a remote condenser located at a higher elevation, as commonly encountered when the condenser is on a roof and the compressor and receiver are on grade level or in a basement equipment room. In this case, the design of the discharge line is very critical. If properly sized for full load condition, the gas velocity might be too low at reduced loads to carry oil up through the discharge line and condenser coil. Reducing the discharge line size would increase the gas velocity sufficiently at reduced load conditions; however, when operating at full load, the line would be greatly undersized, and thereby create an excessive refrigerant pressure drop. This condition can be overcome in one of the two following ways: 1. Size discharge line for the desired pressure drop at full load conditions and install an oil

separator at the bottom of the trap in the discharge line from the compressor. Figure 22. Use a double riser discharge line as shown in . Size line "A" to carry the oil at

minimum load conditions and size line "B" at full load conditions; both lines should have sufficient flow velocity to carry the oil to the condenser.

For more complete information, see the ASHRAE Handbook on Systems. Be aware of the following when fabricating piping:

All oil traps are to be as short in radius as possible. The trap may be fabricated using three 90- degree ells.

•

• •

Use pressure relief valves at the condenser to protect the coil. Use a drain line check valve when the condenser is at a lower temperature than the receiver.

Figure 2, Typical and Double Riser Discharge Piping Arrangement

Typical Piping Arrangement

COMPRESSORRECEIVER

CONDENSER

ReliefValve

LiquidLine

Trap

DischargeLine

Check Valve

Pitch

Pitch

Double Riser Discharge Piping Arrangement

Refrigerant Piping Install piping according to standard accepted refrigeration practice. See Table 1 and Table 2 for discharge and liquid drain line sizes for remote condenser connections. Use only refrigeration grade copper tubing and put dry nitrogen through lines while brazing.

! CAUTION Cautions indicate potentially hazardous situations which can result in personal injury or

equipment damage if not avoided. Do not use soft solder joints. Do not leave dehydrated piping or components open to

the atmosphere any longer than is absolutely necessary due to possible contamination and subsequent equipment damage.

Valves Equip major components with isolation valves and install a relief valve in the discharge line between the check valve and the condenser inlet isolation valve.

8 IOMM A-C Cond

IOMM A-C Cond 9

Discharge Lines Design discharge lines so that refrigerant pressure drop is minimized (high pressure losses cause increased compressor horsepower) and a sufficiently high gas velocity to carry oil through to the condenser coil and receiver at all loading conditions is maintained.

Table 1, Discharge Line Sizing Discharge Line Capacity in Evaporator Tons

R-22 R-134a R-407C R-410A Sat. Suction Temp. Sat. Suction Temp. Sat. Suction Temp Sat. Suction Temp

Line Size Type L Copper OD (in.) 0°F 20°F 40°F 0°F 20°F 40°F 0°F 20°F 40°F 0°F 20°F 40°F

1/2 0.8 0.8 0.8 0.5 0.6 0.6 0.8 0.9 0.9 1.3 1.3 1.3 5/8 1.5 1.6 1.6 1.0 1.1 1.1 1.5 1.6 1.7 2.4 2.4 2.5 7/8 4.0 4.1 4.2 2.7 2.8 2.9 4.1 4.2 4.4 6.2 6.4 6.5

1 1/8 8.0 8.3 8.5 5.4 5.7 6.0 8.2 8.5 8.9 12.5 12.9 13.2 1 3/8 14.0 14.4 14.8 9.4 9.9 10.4 14.2 114.8 15.4 21.7 22.4 22.9 1 5/8 22.1 22.7 23.4 14.9 16.7 16.4 22.5 23.4 24.3 34.3 35.3 36.1 2 1/8 45.7 47.1 48.5 30.8 32.4 34.0 46.5 48.4 50.3 70.8 72.8 74.6 2 5/8 80.4 82.9 85.4 54.4 57.2 59.9 82.0 85.4 88.7 124.5 128.3 131.2 3 1/8 128.2 132.2 136.2 86.7 91.2 95.5 130.5 136.0 141.2 198.4 204.3 209.0 3 5/8 190.3 196.2 202.1 129.0 135.0 142.0 193.3 201.4 209.2 293.9 302.7 309.6 4 1/8 267.8 276.1 284.4 181.0 191.0 200.0 272.6 284.0 295.0 413.8 426.1 435.9 Notes: 1. Source: ASHRAE Refrigeration Handbook: 2. Line sizes based on pressure drop equivalent to one degree F. per 100 equivalent feet 3. Values in Table are based on 105°F condensing temperature. Multiply Table capacities by the factors in

Table 2 for other condensing temperatures. 4. If the line is short, a smaller line size may be used and very long lines may require larger sizes.

Table 2, Condensing Temperature Correction Factor Discharge Line Condensing

Temperature R-22 R-404, R-507 90°F 0.88 0.91 100°F 0.95 -0.97 110°F 1.04 1.02 120°F 1.10 1.08 130°F 1.18 1.16

Table 3, Liquid Line Sizing Liquid Line Capacity

In Evaporator Tons at 100 FPM Velocity Line Size

Type L Copper OD (in.) R-22 R-134a R-407C R-410A

1/2 2.3 2.1 3.8 4.6 5/8 3.7 3.4 7.1 8.6 7/8 7.8 7.1 18.7 22.6

1 1/8 13.2 12.1 37.9 45.8 1 3/8 20.2 18.4 66.2 79.7 1 5/8 28.5 26.1 104.7 125.9 2 1/8 49.6 45.3 317.1 260.7 2 5/8 76.5 69.9 383.7 459.7 3 1/8 109.2 100.0 611.3 733.0 3 5/8 147.8 135.0 907.9 1087.5 4 1/8 192.1 175.0 1281.5 1530.2

R-410A R-410A can have discharge pressures well in excess of 450 psi and special care must be exercised in designing and installing refrigerant components and piping.

10 IOMM A-C Cond

Physical Data

Table 4, Physical Properties of Models ACH, ACL, ACX ACH ACL ACX Model

Size

No. of

RowFans /Row CFM Conn

(in.) Weight

(lbs) Fans /Row CFM Conn

(in.) Weight

(lbs) Fans /Row CFM Conn

(in.) Weight

(lbs)

014 S 1 1 9,900 1 3/8 330 1 8,400 1 3/8 330 1 7,600 1 3/8 330

016 S 1 1 9,500 1 3/8 360 1 8,000 1 3/8 360 1 7,300 1 3/8 360

020 S 1 2 20,500 1 3/8 580 2 17,500 1 3/8 580 2 15,900 1 3/8 580

025 S 1 2 19,800 1 5/8 630 2 16,700 1 5/8 630 2 15,200 1 5/8 630

030 S 1 2 19,000 2 1/8 680 2 16,100 2 1/8 680 2 14,700 2 1/8 680

040 S 1 3 29,700 2 1/8 930 3 25,100 2 1/8 930 3 22,900 2 1/8 930

050 S 1 3 28,500 2 1/8 1000 3 24,100 2 1/8 1000 3 22,000 2 1/8 1000

055 S 1 4 38,600 2 1/8 1210 4 32,800 2 1/8 1210 4 29,800 2 1/8 1210

060 S 1 4 37,000 2 5/8 1310 4 31,200 2 5/8 1310 4 28,400 2 5/8 1310

070 S 1 5 48,300 2 5/8 1510 5 41,000 2 5/8 1510 5 37,300 2 5/8 1510

080 S 1 5 46,200 2 5/8 1640 5 39,100 2 5/8 1640 5 35,500 2 5/8 1640

100 S 1 6 55,400 2 5/8 1950 6 46,900 2 5/8 1950 6 42,600 2 5/8 1950

110 S 1 7 64,700 (2)2 2240 7 54,700 (2)2 2240 7 49,700 (2)2 2240

040 D 2 2 41,000 (2)1 1240 2 35,000 (2)1 1240 2 31,700 (2)1 1240

050 D 2 2 39,600 (2)1 1340 2 33,500 (2)1 1340 2 30,500 (2)1 1340

060 D 2 2 38,100 (2)2 1440 2 32,100 (2)2 1440 2 29,300 (2)2 1440

080 D 2 3 59,400 (2)2 1990 3 50,200 (2)2 1990 3 45,700 (2)2 1990

100 D 2 3 57,100 (2)2 2140 3 48,200 (2)2 2140 3 44,000 (2)2 2140

110 D 2 4 77,200 (2)2 2630 4 65,600 (2)2 2630 4 59,700 (2)2 2630

130 D 2 4 73,900 (2)2 2830 4 62,500 (2)2 2830 4 56,800 (2)2 2830

140 D 2 5 96,500 (2)2 3290 5 82,000 (2)2 3290 5 74,600 (2)2 3290

160 D 2 5 92,400 (2)2 3540 5 78,100 (2)2 3540 5 71,000 (2)2 3540

200 D 2 6 110,90 (2)2 4230 6 93,700 (2)2 4230 6 85,200 (2)2 4230

225 D 2 7 129,40 (4)2 4910 7 109,30 (4)2 4910 7 99,400 (4)2 4910

IOMM A-C Cond 11

Electrical Data Install all electrical wiring according to the National Electrical Code, local codes and regulations. Use copper conductors only. All standard motors have internal inherent overload protectors, allowing contactors to be used instead of starters requiring thermal protectors.

! WARNING Warnings indicate potentially hazardous situations, which can result in

property damage, severe personal injury, or death if not avoided.

There may be more than one source of electrical current in this unit. Do not service before disconnecting all power supplies.

All condensers are furnished with either single-phase or three-phase fan motors, which are identified by the unit dataplate. Electrical leads from each motor terminate at the unit junction box. Field connections must be made from these leads in accordance with local, state and national codes. The motors are wired into a common junction box. Where fan cycling is furnished and factory installed, the motors are completely wired through the control and to the contactors. Check motors for proper rotation and be sure motor voltage and control voltage agree with electric services furnished.

Table 5, ACH Electrical Data, S=Single Fan Row, D=Dual Fan Row 208-230/3/60 460/3/60 575/3/60

Model No. of Rows

No. of Fans per

Row FLA MCA MOPD FLA MCA MOPD FLA MCA MOPD

UNIT kW

ACH 014A S 1 1 7.0 15.0 25 3.5 15.0 15 2.8 15.0 15 1.9

ACH 016A S 1 1 7.0 15.0 25 3.5 15.0 15 2.8 15.0 15 1.9

ACH 020A S 1 2 14.0 20.0 35 7.0 15.0 15 5.6 15.0 15 3.8

ACH 025A S 1 2 14.0 20.0 35 7.0 15.0 15 5.6 15.0 15 3.8

ACH 030A S 1 2 14.0 20.0 35 7.0 15.0 15 5.6 15.0 15 3.8

ACH 040A S 1 3 21.0 22.8 40 10.5 15.0 20 8.4 15.0 15 5.8

ACH 050A S 1 3 21.0 22.8 40 10.5 15.0 20 8.4 15.0 15 5.8

ACH 055A S 1 4 28.0 29.8 45 14.0 15.0 20 11.2 15.0 15 7.7

ACH 060A S 1 4 28.0 29.8 45 14.0 15.0 20 11.2 15.0 15 7.7

ACH 070A S 1 5 35.0 36.8 50 17.5 20.0 25 14.0 15.0 20 9.6

ACH 080A S 1 5 35.0 36.8 50 17.5 20.0 25 14.0 15.0 20 9.6

ACH 100A S 1 6 42.0 43.8 60 21.0 21.9 30 16.8 20.0 25 11.5

ACH 110A S 1 7 49.0 50.8 70 24.5 25.4 35 19.6 20.3 25 13.5

ACH 040A D 2 2 28.0 29.8 45 14.0 15.0 20 11.2 15.0 15 7.7

ACH 050A D 2 2 28.0 29.8 45 14.0 15.0 20 11.2 15.0 15 7.7

ACH 060A D 2 2 28.0 29.8 45 14.0 15.0 20 11.2 15.0 15 7.7

ACH 080A D 2 3 42.0 43.8 60 21.0 21.9 30 16.8 20.0 25 11.5

ACH 100A D 2 3 42.0 43.8 60 21.0 21.9 30 16.8 20.0 25 11.5

ACH 110A D 2 4 56.0 57.8 70 28.0 28.9 35 22.4 23.1 30 15.4

ACH 130A D 2 4 56.0 57.8 70 28.0 28.9 35 22.4 23.1 30 15.4

ACH 140A D 2 5 70.0 71.8 90 35.0 35.9 45 28.0 28.7 35 19.2

ACH 160A D 2 5 70.0 71.8 90 35.0 35.9 45 28.0 28.7 35 19.2

ACH 200A D 2 6 84.0 85.8 100 42.0 42.9 50 33.6 34.3 40 23.1

ACH 225A D 2 7 98.0 99.8 110 49.0 49.9 50 39.2 39.9 45 26.9

NOTE: MOPD = Motor Overload Protection Device.

12 IOMM A-C Cond

Table 6, ACL Electrical Data, S = Single Fan Row, D = Dual Fan Row 208-230/3/60 460/3/60 575/3/60

Model No. of Rows

No. of Fans per

Row FLA MCA MOPD FLA MCA MOPD FLA MCA MOPD UNIT kW

ACL 014A 1 1 6.6 15.0 25 3.3 15.0 15 2.6 15.0 15 1.4

ACL 016A 1 1 6.6 15.0 25 3.3 15.0 15 2.6 15.0 15 1.4

ACL 020A 1 2 13.2 15.0 30 6.6 15.0 15 5.2 15.0 15 2.7

ACL 025A 1 2 13.2 15.0 30 6.6 15.0 15 5.2 15.0 15 2.7

ACL 030A 1 2 13.2 15.0 30 6.6 15.0 15 5.2 15.0 15 2.7

ACL 040A 1 3 19.8 21.5 35 9.9 15.0 15 7.8 15.0 15 4.1

ACL 050A 1 3 19.8 21.5 35 9.9 15.0 15 7.8 15.0 15 4.1

ACL 055A 1 4 26.4 28.1 45 13.2 15.0 20 10.4 15.0 15 5.4

ACL 060A 1 4 26.4 28.1 45 13.2 15.0 20 10.4 15.0 15 5.4

ACL 070A 1 5 33.0 34.7 50 16.5 20.0 25 13.0 15.0 20 6.8

ACL 080A 1 5 33.0 34.7 50 16.5 20.0 25 13.0 15.0 20 6.8

ACL 100A 1 6 39.6 41.3 50 19.8 20.6 25 15.6 20.0 20 8.1

ACL 110A 1 7 46.2 47.9 60 23.1 23.9 30 18.2 20.0 25 9.5

ACL 040A 2 2 26.4 28.1 45 13.2 15.0 20 10.4 15.0 15 5.4

ACL 050A 2 2 26.4 28.1 45 13.2 15.0 20 10.4 15.0 15 5.4

ACL 060A 2 2 26.4 28.1 45 13.2 15.0 20 10.4 15.0 15 5.4

ACL 080A 2 3 39.6 41.3 50 19.8 20.6 25 15.6 20.0 20 8.1

ACL 100A 2 3 39.6 41.3 50 19.8 20.6 25 15.6 20.0 20 8.1

ACL 110A 2 4 52.8 54.5 70 26.4 27.2 35 20.8 21.5 25 10.8

ACL 130A 2 4 52.8 54.5 70 26.4 27.2 35 20.8 21.5 25 10.8

ACL 140A 2 5 66.0 67.7 80 33.0 33.8 40 26.0 26.7 30 13.5

ACL 160A 2 5 66.0 67.7 80 33.0 33.8 40 26.0 26.7 30 13.5

ACL 200A 2 6 79.2 80.9 90 39.6 40.4 45 31.2 31.9 35 16.2

ACL 225A 2 7 92.4 94.1 110 46.2 47.0 50 36.4 37.1 40 18.9

NOTE: MOPD = Motor Overload Protection Device.

Table 7, ACX Electrical Data, S = Single Fan Row, D = Dual Fan Row 460/3/60 208-230/3/60No. of

Fans per Row

No. of Fans

Model FLA MCA MOPD FLA MCA MOPD

UNIT kW

ACX 014A S 1 1 4.8 15.0 15 2.4 15.0 15 1.1ACX 016A S 1 1 4.8 15.0 15 2.4 15.0 15 1.1ACX 020A S 1 2 9.6 15.0 20 4.8 15.0 15 2.2ACX 025A S 1 2 9.6 15.0 20 4.8 15.0 15 2.2ACX 030A S 1 2 9.6 15.0 20 4.8 15.0 15 2.2ACX 040A S 1 3 14.4 20.0 25 7.2 15.0 15 3.4ACX 050A S 1 3 14.4 20.0 25 7.2 15.0 15 3.4ACX 055A S 1 4 19.2 20.4 30 9.6 15.0 15 4.5ACX 060A S 1 4 19.2 20.4 30 9.6 15.0 15 4.5ACX 070A S 1 5 24.0 25.2 35 12.0 15.0 15 5.6ACX 080A S 1 5 24.0 25.2 35 12.0 15.0 15 5.6ACX 100A S 1 6 28.8 30.0 40 14.4 20.0 20 6.7ACX 110A S 1 7 33.6 34.8 45 16.8 20.0 20 7.8ACX 040A D 2 2 19.2 20.4 30 9.6 15.0 15 4.5ACX 050A D 2 2 19.2 20.4 30 9.6 15.0 15 4.5ACX 060A D 2 2 19.2 20.4 30 9.6 15.0 15 4.5ACX 080A D 2 3 28.8 30.0 40 14.4 20.0 20 6.7ACX 100A D 2 3 28.8 30.0 40 14.4 20.0 20 6.7ACX 110A D 2 4 38.4 39.6 50 19.2 20.0 25 8.9ACX 130A D 2 4 38.4 39.6 50 19.2 20.0 25 8.9ACX 140A D 2 5 48.0 49.2 60 24.0 24.6 30 11.2ACX 160A D 2 5 48.0 49.2 60 24.0 24.6 30 11.2ACX 200A D 2 6 57.6 58.8 70 28.8 29.4 35 13.4ACX 225A D 2 7 67.2 68.4 80 33.6 34.2 40 15.6

NOTES: 1. MOPD = Motor Overload Protection Device. 2. Model ACX units are not available in 575 volts.

IOMM A-C Cond 13

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M4

M5

M6

M7

L1L2

L3M

8L1

L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

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T2

T3

T1

T2

T3

T1

T2

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T2

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T2

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T3L3

L2

L1

L3

L2

L1

L3

L2

L1

L3

L2

L1

L3

L2

L1

L3

L2

L1

C8

C7

C6

C5

C4

C3F3

F4F5

F6F7

F8

C8

C7

C6

C5

C4C3

C2

C1

FCP

1

FCP

2

FCP

3

FCP

4

FCP

5

FCP

6

FCP

7

FCP

8

GN

DTE

RM

INAL

BO

AR

D

T1T2

MC

QU

AY P

RE

SSU

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FA

N C

YC

LIN

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NS/

CIR

CU

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FCP

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0/14

0

190/

140

190/

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P #5

, #6

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8

230/

170

230/

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220/

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230/

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220/

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210/

150

ADJU

STA

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GE

(M

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UM

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NG

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5 -2

50#)

(DIF

FER

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0#)

SEE

NO

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14 IOMM A-C Cond

Figure 4, Ten Fan, Two Row, Wiring with Optional Pressure Switch and Fantrol Control

FAN

MO

TOR

IDE

NTI

FIC

ATIO

N

ELEC

TRIC

BO

X

HEADEREND

NO

TE:

1. U

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MU

ST

BE G

RO

UN

DE

D2.

TO

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FIE

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USE

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FO

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AGE

3. A

LL M

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RS

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RE

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P

RO

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4. U

SE

60°

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5. W

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L C

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TRA

NS

FOR

ME

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N6.

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LY

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END

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1-C

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TOR

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OTO

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AN

CY

CLE

PR

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US

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RE

FER

TO

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BEL

AD

JAC

ENT

TO F

US

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OLD

ER

FO

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EP

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AIN

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OR

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CH

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D

L1L2

L3

TER

MIN

AL

BO

ARD

T1T2

T3

460V

OR

230V

INPU

T

F1

24V

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TRANFORMER

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GN

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GN

D

L1 M1

GN

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L1 M1

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GN

D

ELE

CTR

ON

ICFA

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DC

ON

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ELE

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DC

ON

TRO

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VAR

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PE

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ON

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L M

OTO

R

M1

L2R

L1C

S

VAR

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LE S

PEED

CO

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OL

MO

TOR

L2R

L1C

S

M2

L2

T1

T2

L1

L2

T1

T2

L1

MC

QU

AY P

RES

SUR

E F

AN C

YCLI

NG

FAN

S/C

IRC

UIT

5.6

FCP#

1, #

219

0/14

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P#3,

#4

210/

150

FCP#

5, #

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0/16

0FC

P#7,

#8

230/

170

ADJU

STAB

LE R

ANG

E (

MIN

IMU

M R

ANG

E 12

5 - 2

50#)

(DIF

FER

EN

TIAL

RA

NG

E 2

0 - 1

00#)

C10C8 C9

C7

C6

C5

FCP

8

FCP

7

FCP

6

FCP

5

C4

C3

C2C1

FCP

1

FCP

2

FCP

3

FCP

4

GN

DTE

RM

INAL

BO

AR

D

115V

FAN

CO

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0/60

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AX

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V

SEE

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TE 5

F3F4

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F7 C7

C6

C5

C4

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L2

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T2

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L2

L3

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L2

L3

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L1

L2

L3

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T2

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L1

L2

L3

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L1

L2

L3

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T2

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L1

L2

L3

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L2

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L3

L1L2

L3L1

L2

L3

L1L2

L3

L1L2

L3

OP

TIO

N

IOMM A-C Cond 15

Figure 5, Twelve Fan, Two Row, Wiring with Optional Pressure Switch and FanTrol

115V

FAN

CO

NTR

OL

CIR

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H/5

0/60

HZ

15 A

MP

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AX

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FAN

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AN

GE

125

- 25

0#)

(DIF

FER

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RA

NG

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0 - 1

00#)

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8

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7

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FCP

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INAL

BO

AR

DT1

T2

F12

C12

F11

C11

F10

C10

F9 C9

F8 C8

F7 C7

F6 C6

F5 C5

F4 C4

F3 C3

M3

M4

M5

M6

M7

M8

M9

M10

M11

M12

L1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

L1

L2

T1

T2

L3 T3

L1

L2

T1

T2

L3 T3

L1

L2

T1

T2

L3 T3

L1

L2

T1

T2

L3 T3

L1

L2

T1

T2

L3 T3

L1

L2

T1

T2

L3 T3

L1

L2

T1

T2

L3 T3

L1

L2

T1

T2

L3 T3

L1

L2

T1

T2

L3 T3

L1

L2

T1

T2

L3 T3

16 IOMM A-C Cond

Figure 6, Twelve Fan, ACH/ACL/ACX, Wiring with Contactors for Field Installed Control

F AN

MO

TOR

IND

ENTI

FIC

ATIO

N

HEADEREND

ELE

CT R

IC B

OX

NO

TE:

1. U

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MU

ST

BE

GR

OU

ND

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2. T

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FU

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, REF

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3. A

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OTO

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P

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4. U

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AN

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CLE

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OR

DIS

CO

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ECT

SWIT

CH

GN

D

L1L2

L3

TER

MIN

AL

BO

AR

DT1

T2T3

460V

OR

250V

INPU

T

F124

V

L1L2

OP

TIO

NC

1

GN

D

TRANSFORMER

GN

D

L2

L1 T1

T2

P66

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D

L1 M1

M1

ELE

CTR

ICFA

NSP

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CO

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VAR

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L M

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P66

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D

L1 M1

L2 R

L1 C

S

VAR

IABL

E SP

EE

DC

ON

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L M

OTO

R

M2

S

L1 C

L2 R

TER

MI N

AL

BO

AR

DS

FOR

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LD C

ON

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F FA

N C

ON

TAC

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S

TER

MIN

AL

BOAR

D 6

T2 T1C

11C8C7

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C10C9

C6

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TER

MIN

ALB

OA

RD

5

TER

MIN

ALBO

ARD

4TE

RM

INAL

BOAR

D 1

0

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MIN

ALBO

ARD

11

TER

MIN

ALBO

ARD

12

TER

MIN

ALBO

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RM

INA

LB

OA

RD

3

TER

MIN

AL

BO

AR

D 2

TER

MIN

AL

BO

AR

D 8

TER

MIN

AL

BOAR

D 7

TER

MIN

ALBO

ARD

1

T2 T1T2 T1

T2 T1T2 T1T2 T1T2 T1T2 T1T2 T1

T2 T1 T2 T1 T2 T1

FAN

CO

NTR

OL

CIR

CU

IT1P

H/5

0/60

HZ

1 5 A

MP

S M

AX

OV

ER

CU

RR

EN

T P

RO

TEC

TIO

N

M3

M4

M5

M6

M7

M8

M9

M10

M11

M12

L1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

L 1L2

L3

L1L2

L3

L1L2

L3

L1L2

L3

C3

C4

C5

C6

C7

C8

C9

C10

C11

C12F1

2

F11

F10

F9

F8

F7

F6

F5

F4

F3

L1

L2

L3

T1

T2

T3

L1

L2

L3

T1

T2

T3

L1

L2

L3

T1

T2

T3

L1

L2

L3

T1

T2

T3

L1

L2

L3

T1

T2

T3

L1

L2

L3

T1

T2

T3

L1

L2

L3

T1

T2

T3

L1

L2

L3

T1

T2

T3

L1

L2

L3

T1

T2

T3

L1

L2

L3

T1

T2

T3

IOMM A-C Cond 17

Operation

Start-Up Check for proper fan rotation. Air is drawn through the coil on all units. Be sure the fans turn freely. Rotation of the motors and blades should be in a "clock-wise" direction looking at the unit from the blade side. On three-phase units, it may be necessary to reverse two of the three power leads to the unit.

Discharge Gas Pulsation Gas pulsations in a refrigeration system are most commonly associated with the compressor and connecting discharge piping. Variations in the system piping configuration, line sizing, operating pressures and compressor and component mounting all contribute to the presence and magnitude of these pulsations. The vibration and movement of components caused by the pulsations may result in line breakage or damage to the condenser. Install a discharge muffler in the refrigeration piping to eliminate discharge pulsations and the potential for related condenser damage. Follow the recommendations of the compressor or muffler manufacturer when selecting these components.

Discharge Pressure Control Proper application of controls is important to a successful installation. McQuay air-cooled condensers have several options to meet the needs. The capacity of an air-cooled condenser varies with the difference between the entering air dry bulb temperature and the condensing temperature of the refrigerant. Since air temperature varies from summer to winter, the condensing temperature must be kept high enough to ensure proper operation of the refrigerant expansion valve during low ambient air temperature operation, and also allow enough capacity so excessively high condensing temperatures do not occur during high ambient conditions. The low limit of the head pressure is dependent upon the required pressure drop across the thermostatic expansion valve. For normal air conditioning applications, maintain head pressure above a condensing temperature corresponding to 90°F. This corresponds to a normal lower limit of about 60°F ambient air. When operation is required below 60°F ambient air temperature, additional head pressure control will be required. A decrease in ambient air temperature results in a capacity increase in the air-cooled condenser. This capacity increase is directly proportional to the temperature difference between the condensing temperature and the temperature of the ambient air entering the condenser. Air-cooled condensers are often required to operate over a wide range of ambient air temperatures and variable loading conditions so provisions must be made to maintain the overall system balance. Low head pressures cause poor expansion valve operation and poor system operation.

The cycling of condenser fans provides an automatic means of maintaining head pressure control, within reasonable limits, at lower ambient air temperatures. A fan cycling control system allows fans to cycle in sequence by sensing condensing pressures. Short cycling is normally caused by too close a differential in the control settings or setpoints. If field supplied flooding valves are used with fan cycling, set valves to follow the fan cycling. Set pressure switches to at least 35 PSIG differential setting.

Any fan cycle that is less than three minutes is considered short cycling, and could be detrimental to the system. Adjust controls accordingly.

Use optional SpeedTrol™ variable speed fan control for operation below 35°F ambient air temperature

18 IOMM A-C Cond

Fan/Circuit Configuration Fan Rows: All models have either one or dual rows of fans with up to seven fans per row, a maximum total of 14 fans for a dual row unit. The number of fan rows and fans is shown in various tables where appropriate.

Refrigerant Circuits: Dual row condensers have two refrigerant circuits, one for each row of fans and match up with McQuay WGZ and WGS chillers, which have two circuits. The two refrigerant circuits can be optionally equipped with a factory manifold to make one refrigerant circuit.

Single row condensers have a single refrigerant circuit and must be used in pairs on McQuay chillers, each condenser matched to one of the chiller circuits. A pair of single row units is usually only used in the rare case when space requirements dictate two long narrow condensers end to end or when they are in separate locations.

The single row configuration allows more ambient air to flow through the coils than does a unit with a dual row, side-by-side fans and so they often have a little more capacity than a two row unit with the same number of fans. For a given capacity, two single row condensers will cost more than a single dual row unit.

Dual fan, two circuit condensers can be manifolded together to form a single refrigeration circuit.

Control options: One of four control options will have been supplied on any unit. Other special options can be offered to meet individual requirements.

1. Standard Control (Code NN) The standard unit is provided with a contactor for each fan motor. A customer-supplied, and field-installed, control signal from another source is required to energize each contactor based on the condenser pressure. Field wiring between the compressorized product and remote condenser is required. Refer to local codes for this wiring. The contactor control voltage is 115 volts and a transformer is not provided but is an available option. Typical control logic is to start additional fans as condensing pressure increases. Although the parameters of the companion refrigeration system dictates, it is good practice to only use this option only for operation above ambient air temperatures of 35°F. Standard Control Using Chiller MicroTech II® Control Staging The Standard Control (Code NN) or Standard Control with SpeedTrol (Code ST) added can utilize the standard pressure sensing capability of a McQuay chiller’s MicroTech II controller(s) to stage the fans. The WGZ chiller has a single microprocessor with eight fan control digital outputs, four for each refrigerant circuit. The WGS chiller has a separate controller for each of the two circuits with six fan stages, for a total of twelve for the unit.

Field wiring is required between the chiller MicroTech II controller and the fan contactors located in the condenser. The number of connections will depend on the condenser size and arrangement as show in Table 12 or Table 13.

This option uses the standard condenser control included with the condenser and the standard MicroTech II control included with the chiller. Field-supplied interconnecting wiring is the only cost. It does not provide variable speed for operation below 35°F. Use control option #2 to add variable speed for operation from 0°F to 35°F.

IOMM A-C Cond 19

2. Standard Control with SpeedTrol (Code ST) This option is identical to the Standard Control (Code = NN) except the “first on, last off” fan will have a variable speed drive. As the ambient air temperature drops below 35°F, the fan speed will slow down, reducing condenser air flow, to maintain the minimum allowable condensing pressure for the companion unit. A control transformer is provided to power the variable speed drive. Important: This option by itself does not include a method of starting or cycling the balance of fans on the condenser. Some means to do so must be supplied, mounted and wired in the field. The MicroTech II controller on McQuay WGZ or WGS chillers can provide this staging function or some other multi-step controller. Setting: SpeedTrol is performed by a Johnson Controls P66 Electronic Fan Speed Control driving a single-phase fan motor. The control senses discharge pressure and varies the voltage to the motor and hence its speed. Operation is in accordance with the following table.

Table 8, P66 Speed Control Operation Pressure Input Motor Voltage (VAC, True RMS)

Pressure is between 0 psig and the low end of the operating range. 0 to 5 volts, motor off

Start voltage (10% to 40% of line volts, model specific) Pressure is at the low end of the operating range.

Motor voltage (and fan speed) varies directly with pressure from the start voltage to 90% of line volts. Pressure is in the operating range.

A further pressure increase of 20 to 30 psi will increase motor voltage to 97% of the applied volts. Pressure is above the operating range.

The setting of the P66 control must be coordinated with the settings of the fan staging controls, so that the fan is the first fan to start and the last to shut off. To adjust the operating range, locate the adjustment screw on the control’s transducer. The screw can be accessed through the opening in the upper left-hand corner of the control’s base. Turn the screw clockwise to increase, or counterclockwise to decrease, the operating range. One turn equals approximately 35 psig of change.

A P66AAB-9 control is used for R-22. It has an operating (throttling) range of 170 to 230 psig. This 60 psi throttling range is not adjustable. The adjustment moves the entire range up or down. For example, one screw turn clockwise will change the setting from 170/230 psig to 205/265 psig.

20 IOMM A-C Cond

Figure 7, SpeedTrol Operating Range

No fan operationin this

pressure range.Throttling

Range

Operating Range(i.e., 190/250 psig)

Operating RangePlus 20 or 30 psi*

350 psigPressure Input

97%

90%

Mot

or V

olta

ge

0psig

*20 psi for 30 psi Effective Throttling Range (ETR)30 psi for 60 psi Effective Throttling Range (ETR)

The setting of the speed control must be coordinated with pressures switch settings (or MicroTech II staging) so that the fan starts (at minimum speed) when the pressure switch closes, starting the fan. As the discharge pressure increases, the fan speed will increase. Additional fans may stage on and the control should float the # 1 fan speed up and down as the fans stage on, avoiding sudden changes in discharge pressure that can upset unit operation, especially expansion valve control. With the first fan on, set the fan control to start the motor at the same pressure.

Table 9, Troubleshooting Chart Problem Possible Causes Possible Solution

Input pressure is below operating range. No problem, normal operation. No 24 volt control voltage. Check for 24 VAC at control.

Alignment. Schrader valve not depressed sufficiently. No input pressure to control.

Disconnect power. Place a jumper from L to M, and reconnect power. If fan does not run, motor is bad and should be replaced.

Bad fan motor

No fan operation

See Pressure Transducer Troubleshooting following. Pressure transducer problem

Fan stops when pressure reaches the high end of the operating range.

Control is not wired correctly See wiring diagram

Control is not wired correctly See wiring diagram No fan modulation Fan starts at full speed See Pressure Transducer

Troubleshooting following Pressure transducer problem Erratic fan operation Fan motor is cycling on thermal overload Dirty or blocked condenser coil Clean condenser coil

Pressure Transducer Troubleshooting 1. Disconnect 6-pin connector from the right side of control. 2. Place a jumper wire between third pin from the top and the bottom pin on the control,

not the cable. a. If the fan goes to full speed, check for input pressure b. If there is adequate pressure, the transducer is bad and the control must be replaced.

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3. Optional Pressure Switch Control with Control Transformer (Ordering Code = MH) This option provides direct control of discharge pressure through a series of factory-mounted and wired pressure switches (designated as FCP-Fan Cycle Pressure Control-on the wiring diagrams). As the condenser pressure increases, more pressure switches close and start additional condenser fans. Field wiring between the compressorized product and the remote condenser is not required. A control power transformer is included for 115 volt power for the control voltage. The parameters of the refrigerant system dictates, but, it is good practice to only use this option only for operation above ambient air temperatures of 35°F. Setting: The fan pressure switches (FCP) are set per the following table. For example, a setting of 190-140 means that the switch closes at 190 psig starting the fan and opens at 140 psig, shutting it off

Table 10, Electronic Fan Cycling Thermostat Settings S350 Temperature Stage Number of Fans Modules Offset Settings Design

T.D. A350 Setpoint Double Ro ws Single Row 2 3 4 5

30 60

2 4 25 65 20 70 15 75 10 80 30 60 20

3 6 25 65 10 20 70 10 15 75 10 10 80 15 30 60 10 30

4 8 25 65 10 25 20 70 5 20 15 75 5 15 10 80 5 10

60 5 15 30 30 65 5 15 30 5 10 25 70 5 10 30 20 75 5 10 20 15 10 80 5 10 15

30 55 5 15 25 30 25 65 5 10 20 30

6 / 7 12 / 14 20 70 5 10 20 30 15 75 5 10 15 25 10 80 5 10 15 20

NOTES 1. Johnson Controls Style S350 operation. 2. 5° differential set on all modules. All modules set in the “heating” mode.

Table 11, Fan Pressure Switch Settings Control Settings Pressure Switch

Cut-In Settings Number of Fans Design T.D Refrigerant

Single Row

Double Rows PC1 PC2 PC3 PC4 PC5

2 4 20 R134a 147 R22 215

3 6 20 R134a 147 155 245 R22 215

4 8 20 R134a 147 155 231

160 247 R22 215

5 10 20 R134a 147 153 225

156 236

160 247 R22 215

R134a 147 150 223

153 230

157 239

160 247 6 / 7 12 / 14 20 R22 215

NOTES 1. Based on 20º T.D. 2. For R134A set cutout 25 PSIG below cut-in. 3. Fan on header end to remain on whenever compressor is operating.

22 IOMM A-C Cond

4. Optional Pressure Switch Control with Control Transformer & SpeedTrol (Code=VM) This option is identical to the pressure switch control system described above except with the addition of variable speed control to the “first on, last off” fan for each circuit. The fan pressure switches should be set per Table 11. The P66 fan speed controller is set as explained in Section 2, above.

Standard Control (Code NN) or SpeedTrol (Code ST) Using Unit MicroTech II Control Staging The Standard Control (Code NN) or Standard Control with SpeedTrol (Code ST) can utilize the pressure sensing capability of a McQuay chiller’s MicroTech II controller(s) to stage the fans. The WGZ chiller has a single microprocessor with eight fan control digital outputs, four for each refrigerant circuit. The WGS chiller has a separate controller for each of the two circuits with six fan stages, for a total of twelve for the unit.

Field wiring is required between the chiller controller(s) and the fan contactors located in the condenser. The number of connections will depend on the condenser size and arrangement as show in the table below.

Table 12, WGZ Fan Staging and Field Wiring Circuits Fan Stage

1 2 3 4 5 6 7 8 Fans

Circuit #1 Circuit#2 1 3 2 4 - - 4 1 3 5 2 4 6 6 1 3 5 7 2 4 6 8 8 1 3 5 7, 9 2 4 6 8, 10 10 1 3 5, 7 9, 11 2 4 6, 8 10, 12 12

Table 13, WGS Fan Staging and Field Wiring Circuits Fan Stage

Fans Circuit #1 Circuit#2

1 2 - - - - 1 2 - - - - 4 1 2 3 - - - 1 2 3 - - - 6 1 2 3 4 - - 1 2 3 4 - - 8 1 2 3 4 5 - 1 2 3 4 5 - 10 1 2 3 4 5 6 1 2 3 4 5 6 12

Fan Locations 12 10 8 6 4 2

Circuit #2

11 9 7 5 3 1 Electric Panel

Circuit #1

6 5 4 3 2 1 Electric Panel Circuit #1

Flooding Head Pressure Controls Another means of head pressure control is to change the condenser capacity by filling the inside of the condenser with liquid refrigerant. Flooding controls are ideal for condensers operating in low ambient conditions (beyond the limits of fan cycling controls) or under partial load conditions. These controls require additional refrigerant charge (and a receiver) to flood the condenser. This additional refrigerant charge can often be reduced by incorporating the flooded control with one of the fan cycle controls previously described.

IOMM A-C Cond 23

Several styles of flooding valves or combinations of valves are available. Contact the valve manufacturer for specific recommendations.

Refrigerant Charge

The refrigerant charge for summer operation can be found in Table 14. This table also contains the additional charge required by flooding style controls when fan control is not also used. Table 16 contains the recommended flooding charge required when combining fan cycling with flooding valves. The addition of fan cycling to flooded control greatly reduces the required refrigerant charge.

Table 14, Refrigerant Charge. (lbs). R-22 for Flooded Condenser Without Fan Cycling (Times 0.99 for R-134a)

Additional Refrigerant R-22 Charge Required for Flooded Condenser Operation Lbs. For 20°F TD Minimum Ambient at

Condenser

Refrigerant R-22 Charge for Summer Operation,

Lbs.

Model ACH ACL ACX +60 +40 +20 +0 -20

8 7 10 11 11 11 014A-S 10 10 13 15 15 16 016A-S 10 10 13 14 15 15 020A-S 15 15 19 21 22 23 025A-S 29 30 39 43 45 47 030A-S 22 22 29 32 34 35 040A-S 30 29 38 42 44 46 050A-S 70 66 87 96 100 105 060A-S 64 62 83 92 95 99 070A-S 86 83 110 122 127 132 080A-S 102 100 132 147 153 159 100A-S 118 117 155 172 179 186 110A-S 19 20 27 29 31 32 040A-D 29 30 39 44 46 47 050A-D 40 39 51 57 59 62 060A-D 44 44 58 64 67 70 080A-D 58 59 78 86 90 94 100A-D 104 99 131 146 152 158 110A-D 140 131 174 193 201 209 130A-D 125 126 168 186 194 201 140A-D 172 165 219 243 253 263 160A-D 201 201 267 296 308 320 200A-D 236 233 310 343 357 372 225A-D

NOTE: See for factors for Temperature Differences other than 20 degrees.

24 IOMM A-C Cond

IOMM A-C Cond 25

Table 15, Flooded Charge Temperature Difference Factor Design T.D. Ambient, °F

30 25 20 15 10 60 -- 0.38 1.0 1.74 2.46 40 0.59 0.80 1.0 1.19 1.40 20 0.76 0.88 1.0 1.13 1.25 0 0.84 0.91 1.0 1.07 1.16

-20 0.88 0.93 1.O 1.06 1.13

Table 16, Refrigerant Charge for Flooded Condenser With Fan Cycling (lbs.) R-22 (Times 0.99 for R-134a)

25° TD 20° TD 15° TD 10° TD Ambient temperature (°F)

Model ACH ACL ACX 40 20 0 -20 40 20 0 -20 40 20 0 -20 40 20 0 -20

014A-S 7 8 9 9 8 9 10 10 9 10 11 11 13 12 12 12 016A-S 9 12 13 14 11 13 14 15 13 14 15 16 17 18 17 18 020A-S 1 6 8 10 4 8 10 11 7 10 12 13 10 13 14 14 025A-S 2 9 12 15 7 12 15 17 12 16 18 19 17 19 21 22 030A-S 4 17 24 29 14 24 30 34 24 31 36 39 33 38 41 43 040A-S 0 3 10 15 0 10 16 20 0 17 22 25 0 24 27 29 050A-S 0 4 13 20 0 12 20 26 0 21 27 32 0 29 34 38 055A-S 0 0 8 22 0 6 23 35 0 22 38 48 0 37 52 61 060A-S 0 0 11 29 0 8 31 46 0 29 51 63 0 49 71 80 070A-S 0 0 0 15 0 0 17 33 0 0 39 52 0 0 60 70 080A-S 0 0 0 19 0 0 22 44 0 0 50 69 0 0 78 93 100A-S 0 0 0 6 0 0 8 37 0 0 37 69 0 0 66 100 110A-S 0 0 0 0 0 0 0 29 0 0 0 69 0 0 0 108 040A-D 3 12 17 20 9 17 21 23 15 22 25 26 21 27 29 29 050A-D 4 17 24 29 13 24 30 34 22 31 36 39 31 38 41 43 060A-D 5 22 32 38 17 31 39 44 29 40 46 50 41 49 53 56 080A-D 0 5 20 31 0 18 31 40 0 31 42 49 0 44 53 59 100A-D 0 7 27 42 0 25 42 54 0 43 57 66 0 61 71 79 110A-D 0 0 17 44 0 12 47 69 0 43 77 95 0 74 107 119 130A-D 0 0 22 57 0 16 62 91 0 57 102 125 0 99 141 157 140A-D 0 0 0 30 0 0 34 67 0 0 77 105 0 0 120 141 160A-D 0 0 0 39 0 0 44 88 0 0 100 137 0 0 156 186 200A-D 0 0 0 11 0 0 16 74 0 0 74 137 0 0 132 200 225A-D 0 0 0 0 0 0 0 57 0 0 0 135 0 0 0 213

NOTE: See Table 14 for summer charge.

Maintenance

Air-cooled condensing units require a minimum of maintenance. The unit coil will require a periodic cleaning. Clean the unit using a brush, vacuum cleaner, pressurized air stream or a commercially available coil cleaning foam. All of the condenser fan motors have sealed ball bearings and do not need maintenance. If bearings fail, then replace bearings.

Cleaning Instructions ! CAUTION

Cautions indicate potentially hazardous situations, which can result in personal injury or equipment damage if not avoided.

Never clean this unit with an acid-based cleaner. Off-spray can be dangerous to health and the acids are corrosive to aluminum

components.

Clean the finned surface at least every six months; more frequent cleaning may be required if extreme conditions cause clogging or fouling of air passages through the finned surface.

Use Calgon Corporation's CalClean 41352 (or equal). Apply CalClean liberally to entering air and leaving air surfaces of the finned area according to label directions and rinse thoroughly to remove all cleaners.

26 IOMM A-C Cond

•(800) 4321342 • www.mcquay.com IOMM A-C Cond (3/07)

This document contains the most current product information as of this printing. For the most up-to-date product information, please go to www.mcquay.com.

All McQuay equipment is sold pursuant to McQuay’s Standard Terms and Conditions of Sale and Limited Product Warranty.