Air Conditioning Repair Certification (ETI) 2025 – 400 Free Practice Questions to Pass the Exam

The component that is typically installed to increase liquid sub-cooling in a refrigeration system is a liquid to suction heat exchanger. This device enhances the efficiency of the system by allowing the refrigerant vapor returning from the evaporator to absorb heat from the high-pressure liquid refrigerant leaving the condenser. As the liquid refrigerant passes through the heat exchanger, it is cooled further before entering the expansion valve. This process increases the temperature difference between the refrigerant in the heat exchanger and the surrounding low-temperature environment, which enhances the heat transfer efficiency throughout the cycle.

Increased sub-cooling is beneficial because it reduces the chances of vapor entering the expansion valve, ensuring that only liquid refrigerant enters the evaporator. This leads to better cooling efficiency and overall performance of the refrigeration system. The liquid to suction heat exchanger thus plays a vital role in promoting energy efficiency and system reliability.