What does "superheating" refer to in refrigeration?

• A. The process of cooling a liquid below its boiling point
• B. The heating of vapor above its saturation temperature
• C. The cooling of a gas below its dew point
• D. The condensation of vapor back into liquid

Answer: (B)

Superheating in refrigeration refers to the process of heating vapor above its saturation temperature. When a refrigerant vapor is superheated, it rises in temperature beyond the point at which it would normally begin to condense back into a liquid at a given pressure. This is essential in refrigeration systems as it ensures that the vapor entering the compressor is in a state that prevents liquid droplets from causing damage, which can lead to compressor failure.

In a refrigeration cycle, after vaporization, the refrigerant is typically heated further in the evaporator to ensure it is completely in the vapor phase before it reaches the compressor. Effective superheating can improve system efficiency and enhance the overall performance of the refrigeration system.