The laboratory evaluation of the heating mode part-load operation of an air-to-air heat pump

Conference · Tue Jan 01 04:00:00 EST 1985 · ASHRAE Trans.; (United States)

OSTI ID:5505181

Miller, W A

The laboratory evaluation of the part-load Coefficient of Performance (COP) and capacity of an air-to-air heat pump were conducted in a parametric study of heat pump on-time, off-time, and outdoor ambient temperature. A split-system heat pump was instrumented and tested in the heating mode to gain better understanding of the physical processes of the cycling phenomena that degrade heat pump COP and capacity. Improvement in cycling COP and capacity was observed by controlling off-cycle refrigerant migration. Best cycling COP and capacity performance occurred for cycling tests conducted with refrigerant isolated in the indoor heat exchanger during the off-cycle, coupled with 2 min of extended indoor blower operating during the off-cycle. The analysis of loss per on and off cycle revealed refrigerant dynamics to cause appreciable time delays in establishing steady-state heat pump COP.

• Research Organization: Energy Div. of Oak Ridge National Lab., Oak Ridge, TN
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5505181
• Report Number(s): CONF-850606-
• Conference Information: Journal Name: ASHRAE Trans.; (United States) Journal Volume: 91:2B
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320100* -- Energy Conservation
Consumption
& Utilization-- Buildings
AIR SOURCE HEAT PUMPS
AMBIENT TEMPERATURE
BENCH-SCALE EXPERIMENTS
BLOWERS
CAPACITY
COEFFICIENT OF PERFORMANCE
ENERGY LOSSES
FLUID FLOW
FLUIDS
HEAT PUMPS
HEATING
LOSSES
PERFORMANCE TESTING
REFRIGERANTS
SHUTDOWNS
START-UP
STEADY-STATE CONDITIONS
TESTING
THERMAL CYCLING
TIME DELAY
WORKING FLUIDS