Heat pump defrosting operation
This patent describes improvements to the method of defrosting operation of a heat pump having a compressor, an interior heat exchanger, an exterior heat exchanger, an exterior fan for moving exterior air past the exterior heat exchanger, and a thermostatic control means for cycling the compressor on and off in accordance with heating demand. The improvement comprises: operating the exterior fan after the compressor is cycled off by the thermostatic control means; repeatedly measuring the temperature of the exterior heat exchanger after the compressor is cycled of by the thermostatic control means; and deactuating the exterior fan if one of the repeated measurements of the temperature of the exterior heat exchanger indicate a temperature greater than freezing or if one of the repeated measurements of the temperature of the exterior heat exchanger indicate the asymptotic approach to a plateau temperature less than freeing, otherwise continuing to operate the exterior fan.
- Assignee:
- Honeywell Inc., Minneapolis, MN (USA)
- Patent Number(s):
- US 4974418; A
- Application Number:
- PPN: US 7-499089
- OSTI ID:
- 5162981
- Resource Relation:
- Patent File Date: 26 Mar 1990
- Country of Publication:
- United States
- Language:
- English
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