Air Conditioners Explained

Air conditioning is used for cooling and dehumidifying the internal environment of houses, offices and buildings through air conditioners. It basically is a refrigeration mechanism to ventilate, purify and cool the hot dusty air inside buildings. From the outside, air conditioners are rectangular boxes attached to a window or to walls, with the body projecting outside the room. The whole system of heating, ventilation and air conditioning is popularly referred to as HVAC.

Air conditioners work on simple physics principles. There is a fan which circulates the air, a condenser, an evaporator and a compressor. The refrigerant used is mostly Freon, a kind of chlorofluorocarbon (CFC). Freon is the trade name for the CFCs DuPont manufactures.

The mechanism is not very complex. The fan rotates and draws hot air from the room to the air conditioner. Freon is initially in liquid state and has a very low boiling point. It’s kept in a long aluminum tube, at a very high pressure, and can be released through a valve. The valve opens into another component called the evaporator, where it starts boiling because of the low pressure, and since boiling requires heat, it takes the heat from the surrounding air and vaporizes. This Freon is then passed into the condenser, where it is condensed and the heat is released outside the room, then through the compressor for compressing it back into a liquid. This ensures that Freon is reused, and the air is cooled continuously. Also, the filters at the surface of the A/C prevent dust from getting inside it, and from polluting the conditioned air. This is all there is to air conditioning.

Other than A/Cs, Evaporative coolers, are used to condition the air. They simply suck in air from the outside, make it pass through wet sponges, where they lose their heat to the water, and then pass the air to the room.

Air conditioning usually reduces humidity, since the vapor is condensed and drained off. Even though there has been much row over the use of CFCs in A/Cs, because they break down ozone from the atmosphere, these are the best refrigerants made, so far. Conditioned air is said to enhance the efficiency of workers, and has saved several people from heat waves. Whatever the controversies that surround it, air conditioning is here to stay.