What might higher than normal suction pressure and lower than normal high side pressure indicate on a heat pump?

Higher than normal suction pressure coupled with lower than normal high side pressure in a heat pump can indicate problems with the system that affect the refrigerant flow and overall operation. When the reversing valve is faulty, it may not effectively switch the flow of refrigerant between the heating and cooling modes. In heating mode, the system is meant to draw refrigerant from the outdoor coil (suction side) to the indoor coil (high side) after it has absorbed heat outside. If the reversing valve is stuck or malfunctioning, it can disrupt this flow, leading to an imbalance in pressures.

This scenario results in the suction pressure being higher than normal as the refrigerant does not circulate properly to enter the outdoor coil effectively, while the high side pressure drops because the refrigerant is not being adequately compressed or is not moving through the evaporator and condenser coils as it should. Therefore, this condition strongly points to a problem with the reversing valve being the underlying issue.

A clogged filter would typically cause low suction pressure rather than high, as it restricts airflow. An undercharged system often results in low suction pressure. A non-functioning compressor would typically show pressures that are abnormally low on both sides due to the lack of refrigerant circulation. Thus,