Sterling GP Series - Manual (Page 34)

GP Series Portable Chillers Chapter 6: Troubleshooting 34 of 44
Chapter 6: Troubleshooting
Problem Possible cause Solution
No power.
Check main disconnect, fuses, wiring,
and power lead to unit.
Wrong voltage supplied to unit.
Voltage must be within plus or minus
10% of nameplate rating.
Defective on/off switch. Replace.
Replace control circuit fuse.
Check transformer.
Control circuit fuse blown.
Check for a short circuit.
Defective control transformer. Replace.
Piping flow switch circuit open.
Add water or water/glycol solution as
required.
Unit does not run.
Pump motor off on overload. Reset and test.
Leaving fluid setpoint set higher
than temperature of liquid in
system.
Lower the leaving fluid temperature
below the leaving temperature you
desire.
Defective leaving fluid sensor
High/Low thermostat.
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.
Compressor internal overload or
fuses are open.
Check for open fuses and loose
compressor electrical connections.
Compressor contactor holding coil
open.
Repair or replace.
Defective compressor auxiliary
contact.
Repair or replace.
Pump runs; compressor does not.
Broken wire in the compressor
control circuit.
Locate and repair.
Plugged Y-strainer Clean
Hot gas not coming on
Replace relay board on control bed hot
gas coil
Pump runs, compressor cycles at
short intervals.
Low water flow
Install bypass between to-and-from
process line
Water/glycol mixture inadequate
for process.
Make sure that the water/glycol mixture
protection is right for the process.
Improperly set leaving fluid
temperature, warning, or fault set
point
Adjust.
Water temperature is too high.
Refrigerant charge is low.
Call service to find and repair the leak,
then have refrigerant added.