What is typically the main purpose of an expansion valve in a refrigeration system?

The main purpose of an expansion valve in a refrigeration system is to control refrigerant flow. This component plays a crucial role in regulating the amount of refrigerant that enters the evaporator. By modulating this flow, the expansion valve ensures that the refrigerant is expanded from a high-pressure liquid to a low-pressure mixture of gas and liquid. This process is essential because it allows the refrigerant to absorb heat in the evaporator effectively, leading to the cooling of the surrounding area.

When the expansion valve properly controls the flow rate of the refrigerant, it helps maintain optimal efficiency in the system. If too much refrigerant enters the evaporator, it can cause flooding and reduced cooling capacity, whereas too little refrigerant would mean insufficient heat absorption and ineffective cooling. Thus, controlling the flow is pivotal for the overall performance and efficiency of the refrigeration system.