What is the role of the expansion valve in an air conditioning system?

The expansion valve plays a crucial role in an air conditioning system by regulating the flow of refrigerant as it moves from the high-pressure side of the system to the low-pressure side. This component is responsible for reducing the pressure of the refrigerant after it leaves the condenser, allowing it to expand and cool before entering the evaporator coil.

By controlling the amount of refrigerant released into the evaporator, the expansion valve ensures that the system operates efficiently, helps maintain the desired temperature, and avoids issues such as flooding or starving the evaporator. This regulation is essential for the proper heat exchange process and overall effectiveness of the air conditioning system.

Other roles mentioned in the incorrect choices do not apply to the function of the expansion valve. For instance, it does not store excess refrigerant, enhance air circulation, or compress the refrigerant; these functions are managed by other components in the system.