Please advice about chillers issues

[M.alshehri]

Good day

I have issue with 2 compressors in my chillers
We are a maintenace company and there is 2 compressor gone
Both compressors under warranty
The manufacture blame the maintenace that there is no oil in the compressor

Please see the below discussion

After replacing Compressor #, there was no freeze alarm, Compressor 3 & 4 were working since two months. If there was any freeze alarm, Chiller should shut-down from safety sensor and re-start only after manual reset. No one re-set manually without informing us!!

>> We discovered the problem of compressor #2 (currently defect one) at the same day of finishing the works of compressor #4 replacement; both compressors were defected at the same time reason.

As mentioned earlier; the cause of Compressor grounding is due to internal mechanical damage because of migration of liquid refrigerant to the Compressor and mixed to oil.
We request you to please verify the Solenoid Valve for any leakage and inlet and outlet temperature sensor.

>> It is immigration of oil due to liquid refrigerant entering the compressor through suction line. I do not understand solenoid valve point.

Absolutely there was no misuse and this case should be treated under Warranty.

 

[itsmoked]

If the solenoid valve leaks then liquid refrigerant will be running thru the system (the evaporator) without being vaporized because there is no called-for demand. That refrigerant will come back to the compressor and cause hydrostatic-lock (slugging) of the compressor - breaking it.

This can also happen if the compressor's block heater is not operating. The compressor's crankcase can fill with refrigerant, again causing mechanical failure. Sometimes the crankcase heater is supposed to run whenever the compressor is not running. Sometimes it runs always. Sometimes it's thermostatically temperature controlled. It depends on your system's design.

No compressor company will warrant a slugged compressor. It's mistreatment like dragging the compressor behind a truck on a length of chain. If it is a new system, whoever set it up or whoever failed to check everything like the block heater operation or checked with gauges to see if the solenoid valve is leaking should probably be providing the warranty service.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[lilliput1]

Built in safeties should shut down the chiller before damage. Check history of alarms. If there were none then safeties were not working. if there were, were they ignored and bypassed?

 

[DrRTU]

It sounds like you have a few issues going on causing the problems. Advise the system type to help out with root cause analysis. Is this an air cooled machine, split barrel, compressor type and make/model will help. Oil logging and crankcase heaters are valid causes but we will need more system info. Water / side info is also important – hot water on the evap will move the charge. If compressors are semi, did you pull the heads and inspect? Pump down sequence?