In refrigeration, what does the expansion valve do?

• A. Compresses the refrigerant
• B. Reduces the pressure of liquid refrigerant
• C. Converts liquid to gas
• D. Circulates refrigerant through the system

Answer: (B)

The function of the expansion valve in refrigeration systems is to reduce the pressure of the liquid refrigerant. When the liquid refrigerant passes through the expansion valve, it experiences a drop in pressure, which results in its cooling. This pressure reduction enables the refrigerant to enter the evaporator coil at a lower pressure, which is essential for the absorption of heat from the environment, effectively contributing to the cooling process.

This process is crucial because as the refrigerant expands and its pressure decreases, it transitions into a low-pressure vapor, which then can absorb heat more efficiently in the evaporator. Understanding this function is vital for anyone working with refrigeration systems, as the expansion valve plays a key role in the overall efficiency and operation of the cooling cycle.