Centrifugal chiller showing high cond. pressure in Stndby
Centrifugal chiller showing high cond. pressure in Stndby
(OP)
I work with low pressure Centrifugal chiller (Trane) that is showing that it has exceeded the high condenser pressure. It has been in standby for last couple of months. It could be a sensor problem. but is there any other explanation for this. Thanks in advance.





RE: Centrifugal chiller showing high cond. pressure in Stndby
RE: Centrifugal chiller showing high cond. pressure in Stndby
RE: Centrifugal chiller showing high cond. pressure in Stndby
RE: Centrifugal chiller showing high cond. pressure in Stndby
RE: Centrifugal chiller showing high cond. pressure in Stndby
RE: Centrifugal chiller showing high cond. pressure in Stndby
I'm assuming you mean it has stored a fault condition, in this case an incedence of high condensor pressure.
If so, this can be caused by several things, but not realy mean there is a fault in the chiller.
-If condensor pump stopped or failed while chiller was running, then chiller should have shut down on flow switch. However flow switches are prone to failure, and chiller could then shut down on high condensor pressure due to high water temps. If this is the case, there is noting wrong with the chiller, but there is with the pump....Same can happen when basin water get's too low.
- If however there is air in the chiller, it will also cause it to indicate high condensor temps.
Not sure what refrigerant you are running, but R-11 will rupture the disc at around 116 degrees F....You might be running R-123.....Most discs are designed to rupture at 15 PSIG
Please post what type refrigerant you are using, the ambient temp in chiller room, and the pressure presently indicated in condensor while shut down.
Hopefully you have kept good operating logs. If so, you can review them and look for increasing trends in condensor pressure VS cond sat temp....If you see increase there, then tubes are very dirty or you have an air leak....Also look to see if comp discharge temps have increased over time....On L/P chiller you should be running about 118 degrees F comp discharge.
RE: Centrifugal chiller showing high cond. pressure in Stndby
RE: Centrifugal chiller showing high cond. pressure in Stndby
How about the inlet water temperature to the condenser ? As per design ? or has it gone up due to some other reason (Cooling tower related - like fan not working) ?
HVAC68
RE: Centrifugal chiller showing high cond. pressure in Stndby
RE: Centrifugal chiller showing high cond. pressure in Stndby
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Microprocessor shows the condenser pressure that is direct convert of condenser refrigerant temp to Pressure (No Pressure elemet). The trip comes from a separate pressure element in the condenser. When the high condenser pressure alarm came in, the microprocessor was shown Ref Cond temp to be 86.9 F (-6.6 lbs) but when the pressure was measured from the pressure gauge, it was about 0.5 inHg vacuum (-0.25 lbs). Hope this clarifies.
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Also, we have verified that the purge is working and there is no air in the machine.
RE: Centrifugal chiller showing high cond. pressure in Stndby
RE: Centrifugal chiller showing high cond. pressure in Stndby
RE: Centrifugal chiller showing high cond. pressure in Stndby
RE: Centrifugal chiller showing high cond. pressure in Stndby
RE: Centrifugal chiller showing high cond. pressure in Stndby
Did I understand you correctly, did you put a whole new purge unit on. If so, maybe the restrictor is plugged in pump-out line,or there is so much air that pumpout never shuts off. Regardless, you need to find leaks and repair. Good luck.