Laboratory determination of frosting and defrosting losses for a high-efficiency air-source heat pump having a one-row spine fin outdoor heat exchanger

Conference · Sun Jan 01 04:00:00 EST 1984

OSTI ID:5220887

Miller, W A

A high-efficiency, air-to-air, split-system residential heat pump of nominal 3-ton capacity was instrumented and tested in the heating mode under laboratory conditions. The coefficient of performance (COP) and heating capacity of the system were measured during steady-state, dehumidifying, and frosting-defrosting conditions, with major emphasis placed on the dynamic frosting operation of the system. The study encompassed an evaluation of system and component performance for ambient temperature levels between 8.3 and -8.3/sup 0/C (47 and 17/sup 0/F) and for discrete relative humidity levels ranging from 50 to 90%. The heat pump COP and capacity, measured under frosting conditions, decreased with time because of frost accumulation on the outdoor heat exchanger. Frosting caused greater degradation of heating capacity than did defrosting. Algorithms were developed as functions of time, wet-bulb temperature, and moist air enthalpy and are applicable to modeling of frosting losses calculated in a seasonal performance program.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5220887
• Report Number(s): CONF-840124-5; ON: DE84007537
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320101* -- Energy Conservation
Consumption
& Utilization-- Residential Buildings-- (-1987)
AIR SOURCE HEAT PUMPS
ALGORITHMS
COEFFICIENT OF PERFORMANCE
DEFROSTING
DEHUMIDIFICATION
ENERGY LOSSES
FROST
HEAT EXCHANGERS
HEAT PUMPS
ICE
LOSSES
MATHEMATICAL LOGIC
PERFORMANCE
RESIDENTIAL SECTOR