What A/C component causes refrigerant to change from a high-pressure vapor to a high-pressure liquid?

The condenser is the A/C component responsible for changing refrigerant from a high-pressure vapor to a high-pressure liquid. In the air conditioning cycle, hot, high-pressure vapor enters the condenser from the compressor. As air flows over the condenser coils, heat is released from the refrigerant to the surrounding environment, causing the refrigerant's temperature to drop. This heat exchange process allows the refrigerant molecules to condense and change phase from vapor to liquid while still under high pressure.

This function is crucial for the overall efficiency of the cooling system, as the refrigerant must be in liquid form to return to the expansion valve and continue the cycle by evaporating in the evaporator, where it absorbs heat from the cabin air. The other components listed serve different functions in the A/C system, such as the compressor, which increases the pressure and moves the refrigerant, and the evaporator, which allows for heat absorption to cool the air. The expansion valve regulates the flow of refrigerant into the evaporator but does not perform the phase change that occurs in the condenser.