Stormin Mormon wrote:
With the usual wiring, the compressor and fan come on at the same time. This
also happens in window units; compressor and condensor fan are wired on the
same switch. However, in too cold outdoor weather, this results in too cold
refrigerant feeding into the evaporator. Could easily be sub freezing temp
refrigerant, which would cause evaporator icing. Can also result in poor
liquid to vapor conversion in the evaporator. Leading to liquid return to
the compressor. The restaurant units I've serviced used a pressure control
to turn on the condensor fan. A thermal control could be used, but I've not
seen one.

ICM makes temperature sensing electronic head pressure controls
that I use all the time.

http://www.grainger.com/Grainger/items/4MG75

http://www.part-s-mart.com/store/par...bient-kit.html

http://www.thefind.com/appliances/in...essure-control

[8~{} Uncle Monster