To determine superheat in a refrigeration system, what must you subtract?

To determine superheat in a refrigeration system, it is crucial to understand the relationship between the evaporator saturation temperature and the suction line temperature. Superheat is defined as the temperature of the refrigerant vapor above its saturation temperature at a given pressure.

In a refrigeration system, the evaporator saturation temperature corresponds to the temperature at which the refrigerant begins to vaporize and absorb heat from the environment. The suction line temperature, on the other hand, is the actual temperature of the refrigerant vapor as it returns to the compressor after passing through the evaporator.

By subtracting the evaporator saturation temperature from the suction line temperature, you effectively measure how much the refrigerant vapor has been heated beyond its saturation point. This measurement is essential because it ensures that only vapor enters the compressor, preventing liquid refrigerant from causing damage and maintaining system efficiency.

This understanding of superheat is critical for the proper functioning of refrigeration systems, as it aids in diagnosing issues and ensuring optimal performance.