2-40 HP Portable Chillers Chapter 6: Troubleshooting 42 of 70
Problem Possible cause Solution
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.
Defective or improperly set
High/Low thermostat. Adjust or replace.
Refrigerant low pressure switch is
set too high. Call service to adjust pressure control.
Water temperature is too high.
Refrigerant charge is low. Call service to find and repair the leak,
then have refrigerant added.
Pump running in reverse.
Verify rotation; if running in reverse
rotation, reverse any two main power
leads. Re-verify for correct pump
rotation.
Pump pressure low (refer to curves
for normal pressure for various
pumps). Check for foreign matter. Clean the system.
Pump pressure is too high. Restricted water flow. Check for partially closed valves etc.
Make sure that all lines are properly
sized.
Restricted condenser air. Clean filters.
Clean condenser.
Unit low on refrigerant. Check the refrigerant charge.
Compressor not operating
efficiently. Call service.
Unit runs continuously, but not
enough cooling power.
Unit under-sized for application. Call sales rep.