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Photo of La Palma Mobile Mechanic technician recharging a vehicle AC/Heater system with refrigerant.

AC/Heater system problems become front-of-mind in the long days of summer when you're dying from the heat and the short days of winter when you're freezing.  There's a lot to know about a vehicle's AC/Heater system so that they can be properly serviced.  Here, you'll learn about how an AC system works.

While it might appear counterintuitive, your automobile's cooling system doesn't produce cold air in and of itself.  It draws moisture and heat from the air flowing inside your vehicle so that cooler air remains.  Your vehicle's cooling system consists of a specific refrigerant housed in the compressor.  The AC system pressurizes the refrigerant so that it becomes a liquid. The liquid then transmitted into the condenser, which is like a radiator.

The condenser exposes the liquid to the fresh air filtering outside of your car, which draws out the heat from it.  The heat sends into an expansion valve where it changes into gas on the side of the cooling system that has the most ideal amount of pressure.

The receiver component of the AC system collects the heat and filters out excess water, wetness, and grit.  What remains is a purified refrigerant that transmits into the tubing and through your vehicle's evaporator, which is usually located by the control panel in the traveler console.

Since the refrigerant is now a gas, it can extract heat from the air infiltrating the evaporator so that just cold air flows throughout the interior of the vehicle.  The fans in your vehicle's air conditioning system blow the cold air around the automobile to keep everyone inside comfortable.  The refrigerant returns inside the compressor of your air conditioning system where it becomes a pressurized gas and initiates the process all over once again.

Cooling in cars didn't come true for drivers till Hewlett-Packard began producing the very first automobiles including air conditioning systems in 1939.  At the time, the vehicle manufacturer integrated their cooling systems into the trunk of vehicles rather than the control panel, which meant that motorists had to physically set up or disengage the belt from the compressor if they wanted to turn the air on and off.