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How Air Conditioning Works

Having air conditioning in the car is essential for hot days and muggy weather. It works by reducing any moisture and humidity, as well as cooling the air. This is the same way air conditioning systems are used in buildings.

Air conditioning has four main principles, Evaporation, Condensation, Compression and Expansion.

There are two main points which connect all your actual components of the air conditioning in your which are hard tubing and flexible hoses. The four main principles we mentioned above are the physics as to why it works. There are five main components to the system: Compressor, Condenser, Receiver-Dryer, Expansion Valve and lastly, the Evaporator.

The fluid which is passed around the whole system is called the refrigerant and back in the day it was common to use R-12 in cars, however it was soon discovered to be harmful to the earth’s ozone layer and was soon discontinued – cars now use a refrigerant call R-134A which is much kinder to earth!

Here’s how all the various parts of your car’s air conditioning works:

Compressor: The ‘work horse’ of the whole system, this is powered by the drive belt which is connected to the crankshaft of the engine. As soon as you switch your air-conditioning on this will then pump the refrigerant vapour to the condenser.

Condenser: This is the device which is generally used to change the refrigerant vapour into a liquid. It is then mounted in front of the engine’s radiator and then condensed into a liquid due to the amount of pressure that is forcing it in, generating a generous amount of heat. The heat is then removed from the condenser by air flowing through the condenser on the outside.

Receiver: The newly formed liquid now moves into the receiver-dryer, this is a small reservoir vessel that is for the liquid refrigerant. It removes any excess moisture that may have leaked into the refrigerant. If any moisture does happen to get into the system it can cause havoc, create blockages and mechanical damage.

Expansion Valve: Once the process from the receiver is complete the refrigerant then flows into the expansion valve, which then removes any pressure from the liquid refrigerant so that it can expand and become a vapour in the evaporator.

Evaporator: This is another device which is similar to the cars radiator, it has tubes and fins and you will usually find it mounted inside the passenger compartment. As the cold low pressured refrigerant is passed into the evaporator, it then vaporises and absorbs any heat from the on the passenger’s side. The blower fan then pushes the air over the outside of the evaporator allowing the cold air to circulate around the vehicle.

All air conditioning systems will work on the same principle, possibly even the same components however this may vary when it comes to your vehicle.

Hopefully this has explained how air conditioning actually works. If you have any further questions don’t hesitate to ask one of our fully qualified members of the team! Don’t forget to book in to check your air conditioning is still running smoothly.

Published: Thursday 26th March 2015