Steady-state refrigerant flow and airflow control experiments for a continuously variable speed air-to-air heat pump

Conference · Mon Jun 01 04:00:00 EDT 1987 · ASHRAE Trans.; (United States)

OSTI ID:6234458

Miller, W A

A continuously variable speed, air-to-air split-system residential heat pump of nominal 2 3/4-ton (9.7-kW) capacity was instrumented and tested in the laboratory. The coefficient of performance (COP), capacity of the system, and component efficiencies were measured during steady-state heating- and cooling-mode operation. The indoor blower speed and the refrigerant subcooling at the condenser exit were varied at discrete compressor speeds to determine the best COP as constrained by residential comfort requirements. Heating- and cooling-mode test results showed a 10% improvement in COP for operation with a variable area throttle as compared with a capillary tube throttle. Improved control of refrigerant flow and reduction of the indoor blower speed improved humidity control. As compared with results for capillary tube flow control, the sensible heat ratio was reduced from 0.95 to 0.77 at 15-Hz compressor speed.

• Research Organization: Efficiency and Renewables Research Section of the Energy Div. of Oak Ridge National Lab., TN (US)
• OSTI ID: 6234458
• Report Number(s): CONF-870620-
• Conference Information: Journal Name: ASHRAE Trans.; (United States) Journal Volume: 93:2
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320106* -- Energy Conservation
Consumption
& Utilization-- Building Equipment-- (1987-)
AIR FLOW
AIR SOURCE HEAT PUMPS
BLOWERS
BUILDINGS
COEFFICIENT OF PERFORMANCE
COMPRESSORS
CONDENSERS
CONTROL
COOLING
EFFICIENCY
ENERGY EFFICIENCY
FLUID FLOW
FLUID MECHANICS
FLUIDS
FREQUENCY RANGE
GAS FLOW
HEAT PUMPS
HEATING
HYDRODYNAMICS
HZ RANGE
LIQUID FLOW
MECHANICS
REFRIGERANTS
RESIDENTIAL BUILDINGS
STEADY-STATE CONDITIONS
WORKING FLUIDS