When is a refrigerant considered 'superheated'?

A refrigerant is considered 'superheated' when it has an increase in temperature beyond its saturation point. This means that the refrigerant is in a gaseous state and has been heated beyond the temperature at which it transitions from a liquid to a gas. In practical applications, superheating is important because it ensures that the refrigerant remains in the vapor phase before it reaches the compressor of a refrigeration system, which helps prevent liquid slugging and improves system efficiency.

In thermal cycles, the saturation point is where the refrigerant exists in equilibrium between liquid and vapor states. Any heating beyond this point signifies that the refrigerant is not in equilibrium and is in a superheated state. Superheated refrigerant plays a crucial role in enhancing the efficiency of cooling cycles in systems like air conditioning and refrigeration.