Field-measured cycling, frosting, and defrosting losses for a high-efficiency air-source heat pump
An air-to-air heat pump was installed in an unoccupied single-family residence and operated in a two-year test to characterize dynamic losses in capacity and efficiency due to cycling, frosting, and defrosting. During the heating season, defrosting losses were responsible for 10.2% of the total energy consumption (excluding supplemental electric resistance heating), frosting losses for 3.7%, start-up transient losses for 8.5%, and off-cycle parasitics for 3.3%. The heating cyclic degradation factor, C/sub d/, was estimated to be 0.26. Cooling mode steady-state performance of the heat pump was degraded from the manufacturer's ratings due most likely to a small refrigerant leak resulting in a slight charge deficiency. However, using the site measured performance as the steady-state base, it was found that start-up transient losses accounted for 2.8% of the total energy use and off-cycle parasitics for 4.4%. The cooling C/sub d/ was estimated to be 0.11 on this basis.
- Research Organization:
- Oak Ridge National Lab., TN
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 5589942
- Report Number(s):
- CONF-850606-
- Journal Information:
- ASHRAE Trans.; (United States), Vol. 91:2B; Conference: American Society of Heating, Refrigerating and Air-Conditioning Engineers' semiannual meeting, Honolulu, HI, USA, 23 Jun 1985
- Country of Publication:
- United States
- Language:
- English
Similar Records
Laboratory evaluation of the heating capacity and efficiency of a high-efficiency, air-to-air heat pump with emphasis on frosting/defrosting operation
Laboratory determination of frosting and defrosting losses for a high-efficiency air-source heat pump
Related Subjects
AIR SOURCE HEAT PUMPS
DEFROSTING
ENERGY EFFICIENCY
HEAT LOSSES
PERFORMANCE TESTING
HOUSES
ENERGY CONSUMPTION
CAPACITY
COOLING
FIELD TESTS
FROST
LEAKS
REFRIGERANTS
RESISTANCE HEATING
START-UP
STEADY-STATE CONDITIONS
THERMAL CYCLING
BUILDINGS
EFFICIENCY
ELECTRIC HEATING
ENERGY LOSSES
FLUIDS
HEAT PUMPS
HEATING
ICE
LOSSES
RESIDENTIAL BUILDINGS
TESTING
WORKING FLUIDS
320101* - Energy Conservation
Consumption
& Utilization- Residential Buildings- (-1987)