Expansion valve

Definition

The chiller component that throttles high-pressure liquid refrigerant to a lower pressure, causing part of it to flash and lowering its saturation temperature.

The pressure drop returns the refrigerant to a cold, low-pressure state ready to absorb heat again in the evaporator. The partial flashing to vapor lowers temperature without removing heat. This step resets the cycle so the evaporator can repeat its work.

Related concepts

Pressure control of phase change · Evaporator · Refrigerant cycle

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Part of The Blueprint of Water · 🛠️ operations