What must occur before the formation of liquid in a condenser?

Before a condenser can effectively produce liquid refrigerant, the process of desuperheating must occur. This step is crucial because the vapor refrigerant coming from the compressor is often at a higher temperature than its saturation temperature. Desuperheating involves the cooling of this vapor to bring its temperature down to the saturation temperature.

Only after the refrigerant has been desuperheated can it fully condense into a liquid, as the vapor must be at the appropriate temperature for condensation to happen. The refrigerant will remain in vapor form until it reaches its saturation point, at which point condensation can begin. This understanding is vital, especially in refrigeration systems, because managing these heat transfer processes ensures optimal efficiency and performance of the cooling system.

The other options relate to different stages in the refrigeration cycle but do not directly address the prerequisite step needed before the condensation process can begin in the condenser.