Trane SCWH, SCRH manual Maintenance troubleshooting, Troubleshooting, Hazardous voltage

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Maintenance troubleshooting

Maintenance troubleshooting

Troubleshooting WARNING

Hazardous voltage!

Disconnect all electric power, including remote disconnects before servicing. Follow proper lockout/tagout procedures to ensure the power can not be inadvertently energized. Failure to disconnect power before servicing could result in death or serious injury.

Troubleshooting

Use the following steps and procedures to help correct these common problems.

Problem

Remedy

The entire unit does not operate.

1. Check for blown fuses or tripped circuit breakers. Replace or reset if necessary.

Possible cause

2. Setting may be too high; check unit and reset. Thermostat may be out of calibration

1. Power interruption

or otherwise defective; replace.

2. Thermostat not operating

3. Correct as required.

3.Electrical panel: a) 24-volt transformer defective; b) loose wire

Problem

Remedy

Fan runs but compressor does not start.

1. Check power supply for voltage outside the acceptable voltage range.

Possible cause

2. Check the control unit for loose wires. Firm any loose connections.

1. Low voltage

3. Replace.

2. Remote thermostat

4. Check for loose wire connection, broken or burned contacts. If defective, replace.

3. Compressor contactor open or burned

5. Locate leak and repair. Recharge unit.

4 .High pressure control cutting out unit

6. Tug on wires to see if they will separate from connections. Replace terminals if

5. Refrigerant leak - no gas

necessary.

6. Loose or defective wires.

7. Check for shorts, opens, and grounded. Remove and replace compressor.

7. Compressor shorted, open or burned

8. Remove and replace.

8. Defective compressor

 

Problem

Remedy

Unit held off by safety.

1. Adjust tubes by bending slightly to firm position without touching other unit parts.

Possible cause

2. Level unit base. Fully support base.

1. Unit cutout on high pressure control, set at 3. Check and tighten loose screws.

385 psig

4. Tighten screws on fan wheel shaft.

2. Refrigerant leak

5. Adjust wheel position on motor shaft

3. Air restriction, dirty coils

6. Replace fan motor.

4. Partial restriction in refrigerant system

7. Replace fan bearing.

5. High pressure control

 

6. TXV power element charge loss

 

7. Loose connection in electrical unit

 

Problem

Remedy

Noisy operation.

2. See if unit is low on refrigerant charge. Repair leak and recharge unit.

Possible cause

3. Verify if the air filter is dirty or has an airflow restriction, and correct problem.

1. Copper tubing vibrating

4. Locate restriction by inspecting refrigerant lines for temperature changes. Remove

2. Machine vibrating out of level

restriction, evacuate, and recharge.

 

5. Replace, if defective.

 

6. Evacuate, replace element, recharge.

 

7. Trace and firm up connection.

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PKG-SVX14A-EN

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Contents Installation, Operation, and Maintenance “AO” and later design sequenceOctober Midrange Self-ContainedUnitsExample Warnings and Cautions general informationWarnings and Cautions Special Note on Refrigeration EmissionsMaintenance ……………………………………………25 contentsInstallation…………………………………………………2 Operation…………………………………………………24general Installation informationUnit Airflow Configurations Midrange Model Number DescriptionGeneral Refrigerant Handling Proceduresgeneral Installation informationReceiving and Handling pre-installation Installation considerationsInstallation Preparation Pre-InstallationConsiderationsService Access pre-installation Installation considerations3 through 7.5-tonSCRH/SCWH pre-installation Installation considerations Service Access10 through 15-tonSCRH/SCWH Note Isolators are field-provided Isolator Placementpre-installation Installation considerations 1 7/8Proper Lifting Procedure pre-installation Installation considerationsImproper Unit Lift 3 & 5-tons SCWH/SCRH dimensions &Installation weights vertical discharge SCWHInstallation weights 7.5-tons SCWH/SCRHdimensions vertical dischargeInstallation weights SCWH/SCRHdimensions SCWH/SCRH dimensions & weight, in-lbsSCWH/SCRH Dimensions, in dimensionsInstallation weights SCWH/SCRHInstallation weights Plenumdimensions Hot water coil 3 & 5-tonunitsHot water coil 10 thru 15-tonunits Hot water coil7.5-tonunits dimensionsmechanical Installation requirementsDuct Connections Water PipingInstallation requirements Refrigerant Piping Air-CooledUnits OnlyElectrical Requirements Brazing ProceduresInstallation requirements electricalElectrical Data Calculations Supply Power WiringHazardous Voltage Installation requirementselectrical Table I-ER-1.Model SCWH/SCRHelectrical dataInstallation Checklist installationInstallation procedure Plenum InstallationInstallation requirements Pre-StartupChecklistpre-startup ReceivingUnit Startup Checklist Installation startupUnit Startup Procedures Hazardous voltagesequence of Operation operationSequence of Operation Maintenance information Table M-GI-1.Midrange maintenance general datageneral Maintenance Procedures maintenanceMaintenance procedures Periodic Maintenance ChecklistMaintenance procedures Refrigerant Systemmaintenance Leak TestingMotor Winding Damage maintenanceMaintenance procedures Hazardous Pressuresperiodic Maintenance checklistsPeriodic Checklists Monthly ChecklistMaintenance troubleshooting TroubleshootingHazardous voltage Maintenance troubleshooting Insufficient coolingHazardous voltage typical wiring Maintenance diagramtypical wiring Maintenance diagramPKG-SVX01A-EN typical wiring Maintenance diagramtypical wiring Maintenance diagramPKG-SVX01A-EN Date Literature Order NumberPKG-SVX14A-EN October