Question

You answer a service call for insufficient heat. You find the suction pressure is higher and discharge pressure is lower than normal. Using a digital thermometer, you measure the line entering the reversing valve from the compressor discharge and find 215°F. You then measure the line leaving the reversing valve that connects to the indoor coil and find 185°F. These readings are an indication of_____.

Answer 1

The high temperature difference across the reversing valve in a heat pump system suggests a possible restriction or malfunctioning valve, or an issue with the refrigerant charge.

Step-by-step explanation:

Your findings of higher suction pressure and lower discharge pressure than normal, coupled with a high temperature drop across the reversing valve (from 215°F to 185°F), indicate a problem likely related to the reversing valve or the refrigerant charge. Considering the temperatures, the significant drop means there could be a restriction or a malfunctioning valve that is causing an inefficient transfer of heat. The reversing valve is responsible for changing the direction of the refrigerant flow, which is crucial in switching between heating and cooling modes in a heat pump system. The temperature difference suggests heat is not being transferred effectively due to a possible fault in the valve or associated components, or perhaps an issue with the refrigerant charge being either too low or too high.