Sterling 30RA010-055 Service, Electronic Components, Compressor Replacement Refer to Fig, Cooler

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SERVICE

SERVICE

ELECTRIC SHOCK HAZARD.

Turn off all power to unit before servicing. The ENABLE/OFF/REMOTE CONTACT switch on control panel does not shut off control power; use field disconnect.

Electronic Components

CONTROL COMPONENTS — Unit uses an advanced elec- tronic control system that normally does not require service. For details on controls refer to Operating Data section.

Access to the compressors is through latched panels from beneath the control box on all models or from opposite the coil side (sizes 010-030 only). The front door(s) provide access to the compressor(s) and all components of the refrigeration sys- tem. For size 010-030 units, access to the controls is through the upper latched outer door above the compressor access door. Similarly, the upper center latched door on sizes 032-055 gives access to the controls. Inner panels are secured in place and should not be removed unless all power to the chiller is off.

Compressor Replacement (Refer to Fig. 27-

30)— All models contain scroll compressors and have from one to four compressors. The size 010-030 units are a single re- frigeration circuit while sizes 032-055 are dual circuit. A com- pressor is most easily removed from the front of the unit, de- pending on where clearance space was allowed during unit installation.

Unscrew the junction box cover bolts and disconnect the compressor power and ground connections. Remove the cable from the compressor junction box. Remove the connections from the internal thermostat and high-pressure switch (all com- pressors except SM110) or high-pressure switch connections (SM110 only). Knock the same holes out of the new compres- sor junction box and install the cable connectors from the old compressor. Remove the blockoff channel from below the con- trol box.

Be sure the oil equalization line fitting is removed from the old compressor and installed on the new compressor for those models with dual compressor circuits. The compressors are bolted to the unit basepan. Remove the 4 bolts holding the compressor to the basepan. Save the mounting hardware for use with the new compressor. Carefully cut the compressor suction and discharge lines with a tubing cutter as close to the compressor as feasible. For dual compressor circuits, do NOT disturb the suction line tee at the backside of the compressors. This tee contains a special tube that is required for proper oil return. Remove high-pressure switch and pressure transduc- er(s) if required for compressor removal. Lift one corner of the compressor at a time and remove all the rubber mounting grommets. Remove the old compressor from the unit.

Slide the new compressor in place on the basepan. Lifting one side of the compressor at a time, replace all of the compres- sor mounting grommets. Using new tubing or couplings as re- quired, reconnect compressor suction and discharge lines. Us- ing hardware saved, reinstall the mounting bolts and washers through the compressor feet. Using proper techniques, braze suction and discharge lines and check for leaks. Reconnect oil equalization line on dual compressor circuit models.

Reconnect the compressor power connections and high- pressure switch/internal thermostat wiring as on the old com- pressor. Refer to Fig. 27-30. Following the installation of the new compressor, tighten all hardware to the following specifi- cations. (See Table 30.)

Table 30 — Unit Torque Specification

FASTENER

RECOMMENDED TORQUE

Compressor Mounting

10 to 14 ft-lb (13.5 to 18.9 N-m)

Bolts

 

Compressor Power

24 to 28 in.-lb (2.7- to 3.2 N-m)

Connections

 

Compressor Ground

14 to 18 in.-lb (1.6 to 2.0 N-m)

Terminal Connections

 

Oil Equalization

10 to 13 ft-lb (13.5 to 17.6 N-m)

Line Fitting

 

Cooler

BRAZED-PLATE COOLER HEAT EXCHANGER RE- PLACEMENT — Brazed-plate heat exchangers cannot be repaired if they develop a leak. If a leak (refrigerant or water) develops, the heat exchanger must be replaced. To replace a brazed plate heat exchanger:

1.Disconnect the liquid-in and liquid-out connections at the heat exchanger.

2.Check that the replacement heat exchanger is the same as the original heat exchanger. The unit insulation covers the manufacturer’s part number. Make sure the depths of the replacement and original cooler heat exchangers are the same.

3.Reclaim the refrigerant from the system, and unsolder the refrigerant-in and refrigerant-out connections.

4.Remove the old heat exchanger and the bracket that it is mounted to. The replacement heat exchanger is supplied attached to a new mounting bracket and is fully insulated. It also includes a cooler heater. Use of the heater is not re- quired unless the original cooler contained a factory in- stalled heater.

5.Install the replacement heat exchanger in the unit and at- tach the mounting bracket hardware to the fan uprights (sizes 010-030) or to the bottom bracket (sizes 032-055) using the hardware removed in Step 4. Reconnect the cooler heater if required.

6.Carefully braze the refrigerant lines to the connections on the heat exchanger. Lines should be soldered using silver as the soldering material with a minimum of 45% silver. Keep the temperature below 1472 F (800 C) under nor- mal soldering conditions (no vacuum) to prevent the cop- per solder of the brazed plate heat exchanger from chang- ing its structure. Failure to do so can result in internal or external leakage at the connections which cannot be re- paired.

7.Reconnect the water/brine lines.

8.Dehydrate and recharge the unit. Check for leaks.

BRAZED-PLATE COOLER HEAT EXCHANGER CLEANING — Brazed-plate heat exchangers must be cleaned chemically. A professional cleaning service skilled in chemical cleaning should be used. Use a weak acid (5% phos- phoric acid, or if the heat exchanger is cleaned frequently, 5% oxalic acid). Pump the cleaning solution through the exchanger, preferably in a backflush mode. After cleaning, rinse with large amounts of fresh water to dispose of all the acid. Cleaning materials must be disposed of properly.

The factory-installed strainer screen in front of the water/ brine inlets of the heat exchangers should be cleaned periodi- cally, depending on condition of the chiller water/brine.

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Contents SAFETY CONSIDERATIONS CONTENTS GENERALSterlco Comfort Network SCN Interface — MAJOR SYSTEM COMPONENTSControl Module Communication Table 1 — Unit SizesTable 2 — Thermistor Designations Table 3 — Status SwitchesTable 5 - SCN Communication Bus Wiring Table 4 - Output RelaysLEGEND FOR FIG. Page Page Fig. 3 — Wiring Schematic 30RA010-018 30RA010-018AQUA SNAPFig. 3 - Wiring Schematic 30RA010-018cont AQUA-SNAPLOW VOLTAGE CONTROL SCHEMATICSEE NOTE SEE NOTE Fig. 4 - Wiring Schematic 30RA022-030 30RA022-030AQUA SNAPFig. 4 - Wiring Schematic 30RA022-030cont AQUA-SNAPLOW VOLTAGE CONTROL SCHEMATICFig. 5 — Wiring Schematic 30RA032-040 30RA032-040AQUA SNAPFig. 5 — Wiring Schematic 30RA032-040cont AQUA-SNAPLOW VOLTAGE CONTROL SCHEMATICFig. 6 — Wiring Schematic 30RA042-055 30RA042-055AQUA SNAPFig. 6 — Wiring Schematic 30RA042-055cont AQUA-SNAPLOW VOLTAGE CONTROL SCHEMATICREMOTE CONTACT SW1 OFF ENABLE OFF SW2 ON Fig. 7 — Main Base BoardESCAPEENTER MODEFig. 9 — Typical Space Temperature Sensor Wiring Fig. 11 - Energy Management Module CEPL130351100/100 Fig. 12 — Deadband Multiplier R-22Maneurop Compressor Fig. 13 — Operating Envelope forFig. 14 — 30RA Condenser Fan Sequence Cooling Set Point Select Table 8 — Control Methods and Cooling Set Points Service Test See Table 11 — Both main powerand control circuit power must be on Fig. 16 — Scrolling Marquee DisplayOptional Factory-InstalledHydronic Package — •Cooler Pump Control CPC Configuration, OPT1 ON Fig. 17 — Dual Chiller Thermistor Location Table 9 — Marquee Display Menu StructureTable 10 — Run Status Mode and Sub-ModeDirectory SUB-MODE Table 12 - Temperature Mode and Sub-ModeDirectory Table 14 — Set Point and Sub-ModeDirectory Table 13 — Pressure Mode and Sub-ModeDirectoryTable 15 — Inputs Mode and Sub-ModeDirectory KEYPAD Table 16 — Outputs Mode and Sub-ModeDirectorySUB-MODE DISPLAYITEM SUB-MODEKEYPAD DISPLAYITEM SUB-MODEKEYPAD DISPLAYTable 18 — Time Clock Mode and Sub-ModeDirectory PER.3 SUB-MODE Table 20 — Alarms Mode and Sub-ModeDirectory Table 19 — Operating Mode and Sub-ModeDirectoryKEYPAD ENTRY SUB-MODEITEM DISPLAYRSET DISP Table 23 — Operating Modes Table 24 — Example of Reading and Clearing Alarms Table 25A — 4-20mA ResetTable 26B — Configuring Return Temperature Reset Fig. 19 — Outdoor-AirTemperature Reset Fig. 18 — Standard Chilled FluidTemperature Control — No Reset Fig. 20 — Space Temperature ResetFig. 21A — 4- to 20-mADemand Limiting Fig. 21B — Cooling Set Point 4 to 20 mATROUBLESHOOTING Table 27 — Configuring Demand LimitRecommended that system be filled with an appro Table 28 — Troubleshootingand fluid tubing Fig. 22 — Component Arrangement — 30RA010-030 FU — Fuse GND — GroundFig. 23 — Component Arrangement — 30RA032-040 FU — Fuse GND — GroundFig. 24 — Component Arrangement — 30RA042-055 FU — Fuse GND — GroundNOTES LEGEND Table 29 — Alarm and Alert Codes Table 29 - Alarm and Alert Codes cont Table 29 — Alarm and Alert Codes cont ALARMTable 29 — Alarm and Alert Codes cont ALARMTable 29 — Alarm and Alert Codes cont ALARMTable 30 - Unit Torque Specification SERVICECompressor Replacement Refer to Fig Electronic ComponentsFig. 29 — Compressor Location — 30RA010-030 Fig. 28 — Compressor WiringFig. 27 — Typical Compressor Mounting — All Sizes Fig. 30 — Compressor Location — 30RA032-055Condenser Section and Coils Table 31 - Oil ChargeFig. 32 — Condenser-FanMounting Fig. 31 — 30RA Access PanelsCheck Refrigerant Feed Components Fig. 33 — Condenser-FanPosition Standard FanCompressor and Unit Protective Devices Table 32 — Factory Settings, High-PressureSwitch Fixed Check Unit SafetiesCOOLER FREEZE-UPPROTECTION TEMP TEMP For Thermistor T10 For Thermistor T10 Fig. 35 — Fluid-SideTemperature Sensors T1 and T2 Main Base Board, J8 ConnectorFig. 36 — Thermistor Connections to PROGRAMMING Mode •P50: FAULT HISTORY — Last 8 faults Table 37 - Fault Codes•P51: SOFTWARE version PARAMETERS Table 39 — Replacement Modules PRE-START-UP MAINTENANCEMinimum Loop Volume System CheckOperating Limitations Table 41 — Temperature Limits for OPERATION SEQUENCEStandard 30RA Units CIRCADIO Circuit A Discrete Inputs/Outputs APPENDIX ASCN Tables A_UNIT General Unit Parameters CIRCA_AN Circuit A Analog ParametersCIRCB_AN Circuit B Analog Parameters CIRCBDIO Circuit B Discrete Inputs/OutputsOPTIONS Unit Parameters DUALCHIL Dual Chiller Configuration Settings ALARMDEF Alarm Definition TableDISPLAY Marquee Display SETUP BRODEFS Broadcast POC Definition TableOPTIONS1 Options 1 Configuration OPTIONS2 Options 2 ConfigurationRESETCON Temperature Reset and Demand Limit SCHEDOVR Timed Override SetupSETPOINT UNIT ALARMS: Maintenance DisplayMAINTENANCE CURRMODS: Maintenance Display DUALCHIL: Maintenance DisplayLEARNFNS Maintenance Display LOADFACT: Maintenance DisplayPM-PUMP:Maintenance Display PM-COIL:Maintenance DisplayPM-STRN Maintenance Display RUNTEST: Maintenance Display TESTMODE: Maintenance Display STRTHOUR Maintenance DisplayVERSIONS: Maintenance Display WSMDEFME: Maintenance Display APPENDIX B FACTORY SETTINGS FOR COMPRESSOR, FAN, PUMPAND MANUAL STARTERS AND MANUAL STARTERS cont FACTORY SETTINGS FOR COMPRESSOR, FAN, PUMPAPPENDIX C DataPort, DataLink, BAClink Object DefinitionOPTIONS SETPOINTII. Preliminary Equipment Check START-UPCHECKLIST FOR 30RA LIQUID CHILLERRemove and use for Job File I.Project Information Design InformationIII. Unit Start-Up Start and Operate Machine. Complete the FollowingCL-3 COMMENTS Record Software Versions MODE — RUN STATUSCL-4 OPTIONS1 Options Configuration UNIT Configuration SettingsIII.Unit Start-Upcont III.Unit Start-Upcont OPTIONS2 Options ConfigurationRSET Reset Configuration Settings CL-6SETPOINT SLCT Setpoint and Ramp Load ConfigurationIII.Unit Start-Upcont CL-7Service Test Mode and Sub-ModeDirectory III.Unit Start-Upcont
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