HVAC Excellence Commercial Air Conditioning Exam Practice – Complete ESCO Certification Prep 2026

In a refrigeration cycle, the conversion of liquid refrigerant to gas occurs in the evaporator. The primary function of the evaporator is to absorb heat from the surrounding environment, which causes the liquid refrigerant to evaporate into a gas. As the refrigerant evaporates, it absorbs heat, resulting in a cooling effect that can be used in air conditioning or refrigeration applications.

This phase change from liquid to gas is essential for the cycle because it enables the refrigeration system to effectively remove heat from the area being cooled. The refrigerant, now in a gaseous state, then flows to the compressor, where it will be pressurized before entering the condenser, completing the cycle.

The other components play different roles: the compressor increases the pressure of the refrigerant gas, the condenser releases heat to the environment and converts the gas back to a liquid, and the expansion valve regulates the flow of refrigerant into the evaporator but does not facilitate the phase change from liquid to gas.