PO-86-02-4 -- A Refrigerant Enthalpy Method for Measuring Reversing Valve Heat Transfer

Techniques for measuring refrigerant enthalpy at four stations around a reversing valve are described. A heat flow balance is used to calculate heat flow conducted through the valve materials of construction. An analytical method for minimizing the effects of internal leakage on the calculated heat transfer is developed. Data are presented for 6-ton valves and 10-ton valves from two major manufactures. It is concluded that refrigerant enthalpy change can be an acceptable measure of reversing valve heat transfer with internal leakage rates currently typical in the industry.

Units: Dual