How Do Air Conditioners Work?Written by Duncan under Air Conditioners, General | No Comments
Air conditioners have become so entrenched in our everyday lives it’s hard to imagine getting along without them. That blast of fresh crisp, clean air we receive after getting into a baking hot car that’s been sitting in the sun for hours is priceless. Similarly the sudden boost in focus, concentration and enthusiasm that rushes through us when the air-con system is switched on at work simply makes life that bit easier. Overly hot or stuffy environments can cause drowsiness, nausea and lack of alertness, which doesn’t exactly aid your productivity. Research into this has lead many businesses to install air-con units in their work place and they are now a legal requirement in some industries.
So air conditioning has come on leaps and bounds, but have you ever wondered exactly how these gizmos turn your stuffy, unpleasant sweatbox into a chilled out heaven of tranquility? You might imagine that blasting out cold air is a simple process, but it is much more complex than a glorified hair-dryer. Whether they are through the window or wall units or portable air conditioners, they don’t in fact produce their own cold air. Rather they suck in the stagnant air in the environment and recycle it, reproducing it at a lower temperature.
To go into slightly more detail, an air con unit contains a loop of refrigerant gas that expels heat when compressed and absorbs heat when expanded, thus transferring the heat from the room outside. The air cools when it passes over the surface previously cooled by the refrigerant gas. When that refrigerant gas expands in the loop, a fan sucks in warm air from the room and blows it onto the cold coils, reducing its temperature (think of it as the opposite of what happens in a fan heater). In the loop, the warmed expanded gas is pumped to a compressor where it is “squashed”. As it’s squashed the heat is expelled and blown out the unit by another fan. In a portable air conditioner the hot air is pumped outside through a hose and in a wall-mounted air conditioner the outside unit does this. The compressed gas is then pumped back into the loop where is expanded again and so the process continues. This system is the same as the one used in a fridge or freezer.
This is the basic system every air-con unit is based around, though as a rule of thumb, the bigger the unit, the more complex the innards. Different types and sizes of units are used for different proposes. For example, the unit found in a shopping mall will work differently to that of an in-car system, though they both operate on the same basic principles and even a portable air conditioner will use similar technology. Unfortunately this type of air-conditioner will slowly be phased out over the coming years, making way for more eco-friendly versions because the Freon gas used as the refrigerant is harmful to the ozone layer. So don’t say goodbye to your faithful desk fan just yet!