What is the function of the evaporator in an air conditioning system?

The evaporator plays a critical role in an air conditioning system by changing a low-pressure liquid refrigerant into low-pressure gas. This process is essential for cooling. As the refrigerant flows through the evaporator coils, it absorbs heat from the surrounding air or space. This heat absorption causes the refrigerant to vaporize, transitioning from liquid to gas. The evaporation process not only cools the air that is circulated throughout the living space but also enables the refrigerant to pick up more heat, allowing for continuous operation of the cooling cycle.

In contrast, the other functions described do not occur within the evaporator. The conversion of high-pressure liquid to low-pressure liquid is typically associated with the expansion valve or metering device, rather than the evaporator. Storing refrigerant is a function related to the receiver or accumulator, which holds excess refrigerant. Preventing liquid from entering the compressor is the role of a liquid line solenoid or other components designed to ensure only vapor reaches the compressor, thereby safeguarding its operation.