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Expansion Valve: Description and Operation

THERMAL EXPANSION VALVE DESCRIPTION

The expansion valve regulates the flow of liquid refrigerant into the core of the evaporator. As the condensed liquid refrigerant is released through the expansion valve, the refrigerant pressure decreases considerably. As the pressure drops, the refrigerant temperature also drops. Refrigerant passing through the expansion valve is transformed from a high-pressure, medium-temperature liquid into a low-pressure, low-temperature liquid.