Experimental tests were made to determine the heat transfer loss from heat pump reversing valves by a change in refrigerant enthalpy test method. The investigation is limited to the heat transferred to the refrigerant suction stream. Values of a parameter using the enthalpy change per temperature difference driving force were found for various combinations of materials, including brass, steel, stainless steel, and copper tested with valves of a constant size.

A coefficient based on the above enthalpy change is used to compare the various reversing valve constructions. Variations in body and tube materials made significant changes in heat transferred to the refrigerant suction stream.

Units: I-P