Patent ID: 6149066
Filing Date: 2000-11-21
Classification: F24D,F24F,F25B,G05D,Y02B

Abstract:
A heat pump system, comprising:outdoor and indoor heat exchange coils with associated fans;a compressor;an expansion device;means for reversing the flow of refrigerant for purposes of selecting between heating, cooling, and defrost modes of operation;supplemental heating means for heating an air stream passing from the indoor coil to an air supply duct, said supplemental heating means comprising an adjustable output heating element;an indoor thermostat having a first set point for initiating heat supplied by the indoor coil and a second set point for initiating additional heat supplied by the supplemental heating means;means for determining the coil discharge temperature of the air stream heated by the indoor coil at a position between the indoor coil and the supplemental heating means; andcontrol means for selectively energizing the adjustable output heating element in response to the coil discharge temperature, independent of the second set point of the indoor thermostat.