An inefficient compressor is indicated by what combination of head pressure and suction pressure?

An inefficient compressor is best indicated by a combination of lower than normal suction pressure and higher than normal head pressure. When the suction pressure is lower than expected, it suggests that the compressor is struggling to draw in enough refrigerant vapor, which can be caused by issues such as a blockage in the evaporator or insufficient refrigerant charge. This insufficiency prevents the compressor from operating efficiently, as it requires more effort to compress the vapor.

On the other hand, a higher than normal head pressure indicates that the compressor is working harder than it should to expel the condensed refrigerant. This could be due to a few reasons, such as a dirty condenser coil or high ambient temperatures affecting heat rejection.

The combination of these two abnormal pressures signifies that the compressor is unable to perform its job efficiently, resulting in increased energy consumption and decreased cooling performance. Identifying these pressure imbalances is crucial in diagnosing compressor inefficiencies and taking corrective actions to restore normal operation.