Testing AC in cold weather

Originally Posted By: James D Mosier
This post was automatically imported from our archived forum.



Why can’t AC units be tested under 65 degrees?


The AC in my car comes on every time I use the defrost even when it's -10 outside? Works pretty darn good too.

Thanks!


--
Jim Mosier

Originally Posted By: wrobedeau
This post was automatically imported from our archived forum.



Most compressors are hermetic and meant to contain gas on the suction side of the compressor which is the metal can containing the compressor. In cool weather refrigerant migrates to the compressor and condenses as a liquid. Turn on the cooling and the liquid is drawn into the compressor resulting usually in damage to the valves. It can also lock the compressor up to where it cannot be started. This can be over come if a crankcase heater is installed on the compressor to provide heat to drive the refrigerant out. Most domestic systems do not have crankcase heaters.


Automotive compressors are open. The liquid is usually contained in the condenser which is in front of the radiator. When cool outside more liquid goes to the condenser. Most also have some type of accumulator ahead of the compressor. There is considerably less chance of liquid getting to the compressor.

Bill Robedeau


Originally Posted By: James D Mosier
This post was automatically imported from our archived forum.



Thanks Bill



Jim Mosier