The air conditioner in a car generally converts heated air into cooler air by eliminating any heat and moisture. The high-pressure side of the air conditioning system is controlled by the compressor, which constricts refrigerant and forces it into a high-pressure state, causing it to liquefy.

The refrigerant then goes to the condenser through high-pressure lines, where it is exposed to fresh air from outside the car and absorbs heat from the liquid.

The liquid then goes into the orifice tube/expansion valve, where it is changed into a gas and introduced to the low-pressure side of the A/C system, where it is removed or collected by the accumulator or receiver dryer.

The clean refrigerant gas then goes through tubing into the evaporator, where it absorbs heat from the air passing through the fins of the evaporator to produce cool air. The colder air is forced into the cabin through the vehicle’s vents by fans. The refrigerant then returns to the compressor, where it is re-gasified to begin the process all over again.