Heat pump defrosting operation
US4974418A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 1990 |
| Grant date | Dec 4, 1990 |
| Priority date | — |
| Expiry date | Mar 26, 2010 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25D21/006
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
The present invention is a technique for a defrosting operation of a heat pump. External air provides the heat for defrosting the exterior heat exchanger by operating the exterior fan during times when the compressor is not operating, the temperature of the exterior heat exchanger is below freezing and the exterior air temperature is above freezing. In accordance with one embodiment of the present invention the temperature of the exterior heat exchanger and the exterior are measured via separate temperature sensors. In accordance with an alternative embodiment, the exterior heat exchanger temperature is measured via a single temperature sensor and the exterior fan is operated for a predetermined interval of time after the compressor is stopped. Thereafter the exterior fan is operated only so long as the temperature remains at freezing. In a still further embodiment, the exterior fan is operated only so long as it remains less than or equal to freezing and does not reach a plateau at less than freezing. The operation of the exterior fan after deactuation of the compressor may be inhibited throughout an interval of time, if the plateau temperature was less than freezing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.