In a typical vapor-compression air conditioning system, where does the refrigerant change from gas to liquid?

In a typical vapor-compression air conditioning system, where does the refrigerant change from gas to liquid?

• A. Condenser
• B. Evaporator
• C. Compressor
• D. Filter

Answer: (A)

Gas changes to liquid in the condenser. After the compressor, the refrigerant is a hot, high‑pressure gas. It enters the condenser, where it rejects heat to the surrounding air (or cooling water). As it loses heat, its temperature drops to below its boiling point at that pressure, and it condenses into a liquid. The liquid then flows on to the expansion valve, where its pressure is reduced and it proceeds to evaporate in the evaporator to continue the cycle. The evaporator is where liquid becomes gas, not where gas becomes liquid, which is why condensation happens in the condenser.

Gas changes to liquid in the condenser. After the compressor, the refrigerant is a hot, high‑pressure gas. It enters the condenser, where it rejects heat to the surrounding air (or cooling water). As it loses heat, its temperature drops to below its boiling point at that pressure, and it condenses into a liquid. The liquid then flows on to the expansion valve, where its pressure is reduced and it proceeds to evaporate in the evaporator to continue the cycle. The evaporator is where liquid becomes gas, not where gas becomes liquid, which is why condensation happens in the condenser.