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View Full Version : APAC - Carrier Package unit keeps failing



Dingo83
27-07-2012, 10:19 AM
Carrier - APAC Package Unit Model No.P030AHR9AA (2 stage).Stage 1 is now back up and running with after a leak was repaired , liquid line drier changed etc. Approx one week after this leak test was done the unit stopped working with the indoor fan and condenser fan running but no compressors despite both having a 24 volt call to run. After resetting the unit it was found that stage 2 was short of refrigerant and failing on low pressure. Stage 2 has now been disconnected and the low pressure switch bridged out. Over the next 2 weeks a service call came through twice with the unit again in fault again with both indoor / condenser fan running but no compressor. After watching the unit run after been reset it was found the operating pressures were 55/60 psi suction 220/230 psi discharge. All motors amps are ok and airflow across both coils is good.Outdoor temperatures at the time were 8 to 10 degrees celsius and the indoor space temperature was about 19 degrees. The Control PC board & defrost sensors were changed but unit keeps failing ?

Magoo
30-07-2012, 04:11 AM
Start from scratch as to why compressor does not run, go through the control system and prove each operation, possible an internal klixon is holding out compressor.