Copeland Comfort Control (White Rodgers) 1F83C 11PR Thermostat Els PW 17895 this is the standard for this is the standard for protecting expensive scroll and reciprocating hardware in applications exposed to cold ambient conditions where oil viscosity and pump down practicality are critical concerns The Yellow Jacket 22983 is rated for a robust 800 psi maximum working pressure and a 4 providing a wide profile that often covers the footprint of older mechanical or digital thermostats without the need for a wall plate this model is specifically engineered for single stage 1H 1C conventional or single stage heat pump systems without auxiliary heat