Oklahoma Service Technician Practice Exam

The role of an expansion valve in refrigeration is critical to the functioning of the system. It specifically regulates the flow of refrigerant into the evaporator. When the refrigerant enters the expansion valve, it is under high pressure. The valve then allows this refrigerant to expand rapidly into a lower-pressure area in the evaporator. This expansion causes the refrigerant to cool significantly, enabling it to absorb heat from the environment inside the evaporator.

As the refrigerant absorbs heat, it transforms from a liquid to a vapor, which is essential for the refrigeration cycle to operate efficiently. The controlled flow of refrigerant facilitated by the expansion valve is vital to ensure that the evaporator operates properly and maintains the desired temperature.

By managing the amount of refrigerant that enters the evaporator, the expansion valve plays a significant role in optimizing the heat absorption process, thereby enhancing the overall efficiency of the refrigeration system.