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WALK-IN REFRIGERATIONINSTALLATION TRAINING

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Contents  

SECTION 1 OVERVIEW OF RUSSELL SIERRA REFRIGERATION SYSTEM  Page 1.1 Features and Benefits 4

1.2 Conventional Condenser Unit Piping 51.3 Sierra System Condenser Unit Piping 61.4 Sierra System Piping 71.5 EC Motors/Testing 8

SECTION 2 GENERAL INSTALLATION PROCEDURES2.1 Equipment & Accessory Inspection/Inventory 112.2 Verification of Model Numbers, voltage, phase 122.3 Evaporator Placement 132.4 Condensing Unit Placement 152.5 Electrical - Main Power / Control Circuit Wiring 162.6 Refrigerant Line Sizing 232.7 Refrigerant Piping 242.8 Piping Design 322.9 Leak Testing  33

 

SECTION 3 CHARGING AND SUPERHEAT ADJUSTMENT PROCEDURES   3.1 System Evacuation 353.2 Refrigerant Charging Guidelines 37

3.3 Pressure Fan Cycling Control 403.4 TXV / Superheat Adjustment 413.5 System Start-up / Adjustments 423.6 Start-Up Checklist (To be provided by QuikTrip) 43

  SECTION 4 SEQUENCE OF OPERATION / SYSTEM TROUBLESHOOTING  

4.1 Sequence of Operations 2-6 HP 454.2 Sequence of Operations 8 HP 464.3 Troubleshooting 47

SECTION 5 SUGGESTED MAINTENANCE5.1 Maintenance & Inspection Schedule 495.2 Defrost Heater Replacement 52

 

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SECTION 1

Overview of Russell Sierra Refrigeration System

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FLOATING HEAD PRESSURE

=ENERGY SAVINGS +

INCREASED PERFORMANCE

NO LIQUID RECEIVER =

REDUCED INSTALLATION COSTS

REDUCED OPERATING COSTS

INCREASED SYSTEM RELIABILITY

1.1 SIERRA SYSTEM FEATURES & BENEFITS

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1.2 CONVENTIONAL FIXED HEAD PRESSURE CONDENSING UNIT PIPING

Compressor

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1.3 SIERRA SYSTEM CONDENSING UNIT PIPING

“RECEIVER”

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1.4 SIERRA SYSTEM PIPING

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1.5 NEW EC MOTOR vs. OLD PSC MOTOR

PSC MotorEC Motor

Check Motor Mount Attachment- The mounting screws have a

tendency to vibrate loose.

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1.5 EC MOTOR TESTING

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SECTION 2

Installation

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2.1 EQUIPMENT INSPECTION

Inspect shipment for damage and completeness against shipping documents. Report any damage immediately to the General Contractor. Inventory and count accessories to insure all necessary components have been received.

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2.2 VERIFY UNIT MODEL NUMBERS, VOLTAGE & PHASE with PROJECT PLANS

Model Number Detail

R or H = Russell

L = Outdoor unit

H = Type of compressor (H-hermetic, O-Scroll, S-Semi-hermetic, D-Discus)

75 = Compressor horsepower (7.5 hp)

H = Temperature range (H-High temperature, M-Medium temperature, L-low temperature)

22 or 44 = Refrigerant type (22- R22, 44- R404A)

D = Electrical type (C-230/60/1, D-208/230/60/1, E-208/230/60/3, G-460/60/3)

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2.3 EVAPORATOR PLACEMENT

(TOP VIEW - LOW PROFILE TYPE UNIT)

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2.3 EVAPORATOR PLACEMENT (SIDE VIEW)

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2.4 CONDENSING UNIT PLACEMENT

Condensers Mounting:• Mounted on treated 4” x 4” lumber

with roof membrane pads placed beneath the lumber.

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2.5 UNIT ELECTRICAL REQUIREMENTS(MCA / MOPD)

This is the UL tag on the condensing unit providing MCA & MOPD

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2.5 FIELD WIRING REQUIREMENTS - MAIN POWER WIRING

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2.5 FIELD WIRING REQUREMENTS AIR DEFROST CONTROL WIRING

LIQUID SOLENOID VALVE IS FACTORY MOUNTED

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2.5 FIELD WIRING REQUREMENTS ELECTRIC DEFROST

DASHED WIRING (IN FIELD)

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2.5 ELECTRIC DEFROST CONTROL OPTION

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2.5 ELECTRIC DEFROST EVAPORATOR WIRING

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2.6 REFRIGERANT PIPING

LIQUID LINE SUCTION LINE

Minimum distance between condensers is equal to the length of the condenser

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2.6 LIQUID LINE DESIGN CRITERIA

MINIMIZE PRESSURE DROP AT DESIGN CONDITIONS IN ORDER TO MAXIMIZE SYSTEM EFFICIENCY (APPROX. 5 PSIG)

OIL FLOW WILL NOT NORMALLY BE A PROBLEM DUE TO LIQUID REFRIGERANT / OIL MIXTURE

AVOID INSTALLING ADDITIONAL EXTERNAL FILTER DRIERS, BALL VALVES, ETC. SINCE PRESSURE DROP IS CUMMULATIVE

TO HELP MAINTAIN LIQUID SUBCOOLING AND AVOID THE POSSIBILITY OF FLASH GAS AT THE TXV INLET, INSULATE THE LIQUID LINE TO MINIMIZE EXCESSIVE HEAT GAIN WITH 1” INSULATION

ALL EXPOSED REFRIGERATION LINES AND INSULATION SHALL BE PAINTED WITH UV PROTECTIVE PAINT.

ADDITIONALLY, UNDER CERTAIN OPERATING / AMBIENT CONDITIONS, FLOATING HEAD PRESSURE SYSTEMS CAN EXPERIENCE SWEATING OF THE LIQUID LINE THEREFORE IT IS ALWAYS DESIREABLE TO INSULATE THE LIQUID LINE, PARTICULARLY WHERE SWEATING OR CONDENSATE DRIPAGE COULD PRESENT A HAZARD TO THE BUILDING STRUCTURE, PRODUCT OR PERSONNEL!

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MINIMIZE PRESSURE DROP AT DESIGN CONDITIONS WHILE MAINTAINING MINIMUM INTERNAL VELOCITIES TO ENSURE ADEQUATE OIL RETURN BACK TO COMPRESSOR

(LOW TEMP – APPROX. .5 PSIG / MED TEMP – APPROX. 1 PSIG)

OIL RETURN IS CRITICAL!

LOW TEMPERATURE AND A LACK OF LIQUID REFRIGERANT AT THE EVAPORATOR OUTLET INHIBIT OIL RETURN

USE GRAVITY TO ASSIST OIL RETURN WHENEVER POSSIBLE

PITCH ALL SUCTION LINES IN DIRECTION OF FLOW (MIN ¼” FT)

USE “P” TRAPS AT THE BOTTOM OF ALL VERTICAL RISERS

RUN PIPE INSULATION COMPLETELY THROUGH WALK-IN CELING PANEL TO PREVENT SWEATING UNDER PANEL SKINS.

2.6 SUCTION LINE DESIGN CRITERIA

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2.7 REFRIGERANT LINE SIZING

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2.7 REFRIGERANT LINE SIZING

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2.7 ADD THE EQUIVALENT FEET OF TUBING REQUIRED FOR ELBOWS, TRAPS, ETC

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2.7 CONDENSATE DRAIN LINE PIPING

Pitch all drain lines a minimum of 1” per foot – 4” per foot is recommended

Do not reduce line size from fitting size on evaporator

Increase size of drain line for multiple evaporators

Protect drain line from freezing in walk-in freezers

Install P-Trap outside of walk-in

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2.7 TXV SENSING BULB LOCATION

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2.8 OIL FLOW INSIDE A VERTICAL SECTION OF SUCTION LINE

OIL FILM

OIL DROPLETSProperly sized riser will help insure return of oil to compressor – where it belongs

OIL DROPLETS

OIL FILM

FLOW

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2.8 POOR SUCTION LINE DESIGN FOR OIL RETURN

GAS FLOW

OIL FLOWOIL FLOW

Title

Author

File

Revision

Document

Date Sheets1.0 1 of 1

Improper suction line design will cause oil and vapor to separate – reducing

proper oil return to compressor.

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2.8 OIL TRAPPING

A P-Trap must be installed at the bottom of the suction line riser and at every 15’ to 20’ of riser height.

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2.9 LEAK TESTING

FOLLOW EPA REGULATIONS REGARDING THE USE & DISPOSAL OF REFRIGERANTS.

PRESSURIZE SYSTEM WITH REFRIGERANT TO APPROX 25 TO 35 PSI   PRESSURIZE WITH REGULATED NITROGEN TO APPROX 120 TO 140 PSI  ALLOW PRESSURE TO STABILIZE FOR APPROX 30 MINUTES  LEAK CHECK USING SOAP BUBBLES AND / OR ELECTONIC LEAK DETECTOR   CHECK ALL SYSTEM CONNECTIONS AND COMPONENTS (BOTH FIELD AND FACTORY MADE)  IDENTIFY ALL LEAKS, REDUCE SYSTEM PRESSURE TO 0 PSI AND EFFECT REPAIRS  REPEAT ABOVE PROCEDURE UNTIL ALL LEAKS HAVE BEEN LOCATED AND REPAIRED   FINAL PRESSURE TEST SHOULD ALLOW SYSTEM TO REMAIN PRESSURIZED OVERNIGHT TO VERIFY THAT THE PRESSURE REMAINS UNCHANGED

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SECTION 3

Charging & Adjusting

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3.1 SYSTEM EVACUATION

Use the right size pump (minimum 1.2 CFM)

Change the vacuum pump oil frequently

Use a micron vacuum gauge whenever possible

Don’t overlook the importance of a deep vacuum

Use oversized hoses or copper tubing whenever possible

Make sure all system components / piping are accessible to ensure evacuation of the

entire sealed system

Avoid evacuating through Schrader valves or similar restrictions

Evacuate from at least (2) system connection points

Operate the vacuum pump continuously for no less than (4) hours to achieve a maximum

of 400 microns.

Blank off the system and allow to sit for a minimum of 20 minutes. (no measureable

increase in vacuum reading indicates the system is dry and tight)

Break the vacuum with a small amount of refrigerant vapor and proceed to system

charging instructions

Use 3-Stage evacuation - sweep and purge method

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3.1 SYSTEM EVACUATION POINTS

GAUGE PORT

GAUGE PORT

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3.2 SYSTEM CHARGING REQUIREMENTS

KEY POINTS TO REMEMBER:

SIERRA IS A FLOATING HEAD SYSTEM SIERRA HAS NO LIQUID RECEIVER NO ADDITIONAL CHARGE REQUIRED FOR

WINTER OPERATION NO STORAGE CAPACITY FOR “EXTRA”

REFRIGERANT Critical Charge – Clear Sight Glass Only Do not add additional refrigerant

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3.2 SYSTEM CHARGING REQUIREMENTS

(ALL CONDENSER FANS MUST BE ON)

STEP 1

INITIAL CHARGE SHOULD

BE BASED ON A MAXIMUM OF 3 LB’S PER UNIT HP

EXAMPLE:

MODEL RIO301M44

3 HP X 3 LB’S = 9 LB’S

STEP 2

REFER TO SATURATED CONDENSING TEMP VS AMBIENT TEMP ENTERING CONDENSER

LOW TEMP = 15 DEGREES ABOVE AMBIENT AIR

MED TEMP = 20 DEGREES ABOVE AMBIENT AIR

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3.2 SYSTEM CHARGING (EXAMPLE)

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3.3 PRESSURE FAN CYCLING CONTROL ADJUSTMENT

MED TEMP UNITS

125 PSI CUT-IN 95 PSI CUT-OUT

LOW TEMP UNITS

90 PSI CUT-IN 60 PSI CUT-OUT

Sierra Fan Setting

Adjust the pressure fan cycling cut-out to be 30 PSIG above the design suction pressure and the cut-in at 30 PSIG higher differential.

Tech Note: If the design suction pressure is unknown, then for a 35 degF box temp for 404A use 60# cut-out and 90# cut-in.

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3.4 TXV SUPERHEAT - CKECK / ADJUSTMENT

To reduce the superheat, turn the adjusting stem counterclockwise.To increase the superheat, turn the adjusting stem clockwise. When adjusting the valve, make no more than one turn of the stem at a time and observe the change in superheat closely to prevent over-shootingthe desired setting. As much as 30 minutes may be required for the new balance to take place after an adjustment is made.Evaporator Super Heat typically runs 6 to 12 deg. (8 to 10 preferred)Compressor Super Heat Copeland required minimum of 20 deg. (25 to 40 preferred)

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3.5 START-UP CKECK / ADJUSTMENT

Run System for 24 hours before making any adjustments including

Superheat unless there is flood-back to condenser.

Check pressures, temperature, amp draw, pressure switch settings

and Superheat at TXV and compressor.

Once sight glass is clear - NO additional refrigerant is needed.

The Russell Sierra is a CRITICAL CHARGED system –

DO NOT OVERCHARGE

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3.6 START-UP CKECKLIST

Add QuikTrip Start-up Checklist

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SECTION 4

Sequence of OperationsTroubleshooting

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4.1 SEQUENCE OF OPERATION - (2 - 6 HP UNITS)

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4.2 SEQUENCE OF OPERATION(8 HP UNIT)

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4.4 TROUBLESHOOTING

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4.4 TROUBLESHOOTING (CONTINUED)

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SECTION 5

Suggested Maintenance

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5.1 SUGGESTED MAINTENANCE / INSPECTION SCHEDULE FOR SIERRA REFRIGERATION SYSTEM

  (Service / Maintenance to be performed only by a qualified refrigeration service technician)

   The physical inspection of any rotating parts and ALL electrical components should be performed only

after the system has been pumped down and all electrical supplies turned off and locked out.

 

EVERY 6 MONTHS   Visually inspect the entire sealed refrigerant system for any evidence of leaks, line movement or

component damage. Check all flange connection bolts, fittings and line clamps for tightness. Properly “dress” all capillary tubes, control lines and flexible hoses to prevent chafing and potential rub-throughs.

  Inspect the entering air face of the condenser coil for accumulation of dirt and debris. Clean as

necessary and straighten fins as required to ensure proper air flow through the coil.

  Inspect the condenser fan blades and motor mounts for stress cracks, loose set screws, mounting bolts

and resilient clamping rings. Replace any cracked or out of balance fan blades or motors exhibiting excessive shaft end play.

  Check compressor oil level (if equipped with a crankcase sight glass). Maintain at least ¼ to ½ sight

glass during stable system operation.

  Check operation of compressor crankcase heater. Heater should be energized when compressor is off.

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5.1 SUGGESTED MAINTENANCE / INSPECTION SCHEDULE (CONTINUED)

Check the refrigerant charge via the liquid line sight glass at receiver outlet. NOTE: During normal operation bubbles will occasionally appear in the sight glass as the expansion valve(s) modulate open or the condenser fan(s) cycle. This is not necessarily an indication of an undercharged system.

  Tighten all electrical connections. Check operation and condition of contacts of all contactors and relays

and replace as necessary.

  Test all operating and safety controls with an accurate service gauge manifold installed. Confirm actual

control set points agree with recommended values listed in unit operation and installation manual.

  Check operation of unit cooler(s). Refer to items (1) through (3) above for applicable inspection details.

NOTE: Excessive moisture infiltration into conditioned areas may result in unusually heavy frost accumulation that may require periodic manual cleaning of fan blades, guards, or sheet metal housings in order to avoid fan unbalance condition and potentially destructive vibration.

  Record all critical operating pressures and temperatures during stable system operating conditions in the

normal refrigeration and defrost modes. Example; suction, discharge and liquid refrigerant pressures and temperatures, compressor superheat, motor amp draws, etc. Investigate and correct any abnormal readings.

 

 NOTE: The above information is provided only as a general guideline to aid servicing personnel and equipment owners in maintaining SIERRA refrigeration systems. Due to variables in the actual equipment application and / or operating conditions, recommended service intervals may vary.

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5.2 DEFROST HEATER