What does superheat at the compressor inlet refer to?

Superheat at the compressor inlet is defined as the temperature increase of refrigerant above its saturation temperature at a given pressure. In refrigeration systems, the refrigerant is vaporized by absorbing heat as it passes through the evaporator. The vapor reaching the compressor should be entirely in the vapor phase to ensure efficient operation.

When this vapor is heated to a temperature above the saturation temperature corresponding to its pressure, it is referred to as being "superheated." This additional heat ensures that the refrigerant is fully vaporized and enhances the efficiency of the compressor, preventing liquid refrigerant from entering the compressor, which could cause damage.

Understanding superheat is critical for maintaining the performance and reliability of refrigeration systems, as it plays a key role in optimizing energy efficiency and preventing issues like compressor failure.