The expansion valve is a crucial component that plays a key role in regulating the flow of refrigerant through the car’s AC system. It is positioned between the high-pressure and low-pressure sides of the AC system. The expansion valve acts as a valve or metering device that controls the flow of high-pressure, high-temperature liquid refrigerant from the condenser to the low-pressure side, where it can evaporate.
As the high-pressure liquid refrigerant passes through the Expansion Valve, it undergoes a rapid pressure reduction. This causes the refrigerant to expand and transform into a low-pressure, low-temperature gas. The expansion of the refrigerant leads to a significant drop in temperature. This cold refrigerant gas is then circulated through the evaporator coil in the car's AC system. The cold refrigerant gas absorbs heat from the surrounding air as it passes over the evaporator coil. This process cools down the air, which is then blown into the vehicle's interior by the AC blower fan.
You should be aware of these common signs that may indicate a problem with the AC expansion valve: