How does the expansion valve contribute to an A/C system?

The expansion valve plays a critical role in an A/C system by reducing the pressure of the refrigerant as it flows from the high-pressure side to the low-pressure side of the system. When the refrigerant passes through the expansion valve, it experiences a drop in pressure, which causes it to expand. This expansion leads to a decrease in temperature, meaning that the refrigerant becomes colder.

This colder refrigerant is essential because it allows the A/C system to absorb heat from the inside of a building or vehicle more effectively when it reaches the evaporator coil. The refrigerant, now in a low-pressure, cold state, can readily absorb heat, thereby cooling the surrounding air. This process is fundamental to the operation of the air conditioning system, making the expansion valve a vital component in achieving efficient cooling performance.