Patent ID: 6442963
Filing Date: 2002-09-03
Classification: B60H,F25B

Abstract:
Apparatus for purging to atmosphere non-condensables from a volume of refrigerant, the apparatus comprising:a pressure transducer coupled to the volume for measuring the pressure therein; a temperature transducer disposed for measuring the temperature of vapor in the volume; a purge valve coupled between the volume and atmosphere and operable between a closed condition isolating the volume from atmosphere and an open condition permitting exposure of the volume to atmosphere; and a processor operating under control of a stored program for controlling operation of the valve, the program including a purge routine responsive to measured temperature of the volume for determining an ideal vapor pressure in the volume corresponding to the measured temperature, the purge routine being responsive to measured pressure in the volume exceeding a target pressure above the ideal vapor pressure for effecting a controlled operation of the purge valve until the measured pressure drops to the target pressure.