How your car Air Conditioner works

As it pressurizes, it gets hot by absorbing the heat around it. This hot gas is then circulated through a series of tubes that dissipate the heat. Scientifically, the gas removes heat rather than adds cold, but that’s a lesson in physics that doesn’t really matter to us right now. The gas can lose lots […]

As it pressurizes, it gets hot by absorbing the heat around it. This hot gas is then circulated through a series of tubes that dissipate the heat. Scientifically, the gas removes heat rather than adds cold, but that’s a lesson in physics that doesn’t really matter to us right now. The gas can lose lots of its heat. In other words it gets really cold when you reduce the pressure. As it cools it becomes a liquid. This is when you get cold air blowing on your sweaty forehead.

To use this system in a car, it needed very little adaptation from its early applications as a refrigeration device.

Components of Automotive Air Conditioning

Your air conditioning system is made up of a compressor, a condenser, an evaporator (or drier), refrigeration lines and a couple of sensors here and there.

•    Compressor: This is the heart of your a/c system. The compressor is what takes the refrigerant (the gas) and pressurizes it so it will cool the air. It’s run by an engine belt. The compressor also has an electrically operated clutch that turns the compressor on and off as you demand more cool air.

•    Condenser: The condenser is like a miniature radiator, usually mounted at the front of the car right next to your big radiator. Sometimes the condenser will have its own electric cooling fan, too. The hot, compressed air passes through the condenser and gets lots cooler. As it cools, it becomes a liquid.

•    Evaporator: The evaporator is another little radiator that does just the opposite task as the condenser. As the super-cool liquid is passed through its tubes, air is forced through and gets really cold, right before it hits your face. As it warms up again, the refrigerant starts turning back into a gas.

•    Thermal Expansion Valve: You don’t always want to freeze your toes off, so the a/c system has a valve that controls the flow of super-cool refrigerant to the evaporator. This way you can regulate how cold the air blowing on you gets. There are a few types of valves in use these days, but they all do the same thing.

•    Drier or Accumulator: The drier, also known as the receiver-drier, is sort of a safety catch for your system. The compressor is only supposed to compress the gas form of your refrigerant.