Chapter 6: Troubleshooting

Problem

Possible cause

 

No power.

 

 

 

Wrong voltage supplied to unit.

 

 

 

Defective on/off switch.

Unit does not run.

Control circuit fuse blown.

 

 

 

 

Defective control transformer.

 

Piping flow switch circuit open.

 

 

 

Pump motor off on overload.

 

Leaving fluid setpoint set higher

 

than temperature of liquid in

 

system.

 

Defective leaving fluid sensor

 

High/Low thermostat.

 

Compressor internal overload or

 

fuses are open.

Pump runs; compressor does not.

 

 

Compressor contactor holding coil

 

open.

 

Defective compressor auxiliary

 

contact.

 

Broken wire in the compressor

 

control circuit.

 

 

 

Plugged Y-strainer

Pump runs, compressor cycles at

Hot gas not coming on

short intervals.

 

Low water flow

 

 

 

 

Water/glycol mixture inadequate

 

for process.

Water temperature is too high.

Improperly set leaving fluid

temperature, warning, or fault set

 

 

point

 

Refrigerant charge is low.

 

 

Solution

Check main disconnect, fuses, wiring, and power lead to unit.

Voltage must be within plus or minus 10% of nameplate rating.

Replace.

Replace control circuit fuse. Check transformer.

Check for a short circuit. Replace.

Add water or water/glycol solution as required.

Reset and test.

Lower the leaving fluid temperature below the leaving temperature you desire.

Replace.

Allow time to cool and reset, then check for high/low volt-age. It must be within plus or minus 10% of the nameplate rating.

Check for open fuses and loose compressor electrical connections.

Repair or replace.

Repair or replace.

Locate and repair.

Clean

Replace relay board on control bed hot gas coil

Install bypass between to-and-from process line

Make sure that the water/glycol mixture protection is right for the process.

Adjust.

Call service to find and repair the leak, then have refrigerant added.

GP Series Portable Chillers

Chapter 6: Troubleshooting

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Sterling specifications GP Series Portable Chillers Troubleshooting