It is not uncommon to control the compressor with a preasure control instead of a thermostat on refrigeration equipment.
A larger unit that has a liquid line solenoid and a pump down cycle will use a preasure control to control the compressor.
The liquid line solenoid closes - on temp or preasure - and the unit pumps down and shuts off at 15-20# suction.
[This message has been edited by wolfdog (edited 11-02-2003).]
