subject: Some Basic Facts About Your Home Air Conditioning System [print this page] Air conditioners are considered a luxury rather than an essential in most parts of North America. Air conditioning systems are more common in the southern areas and are more common in humid areas than in dry areas. There are probably more air conditioners per capita in Florida than in California, for example. You probably have a good sense already as to how common central air conditioning systems are in your area.
If the outdoor temperature is 70F at night and all the windows in the house are open, the indoor and outdoor temperatures will both be about 70F. As the sun comes up, the outdoor temperature may rise to 85F or 90F. Because of shading, thermal mass, and so on, the house will not heat up as quickly as the outdoors, but it will eventually get just as hot as it is outside. The goal is to keep it more comfortable inside the house than it is outside.
The essential ingredients in an air conditioning system are a fan to blow air around, a cold surface to cool and dehumidify the air, a warm surface and a source of water vapour. In a large system there will also be a tangle of tubes to distribute the air and collect it again.
Notice that the cold surface has two independent jobs to do: it is used to cool the air and it is also used to dehumidify, by condensing water from the air. This means that the air is cooled more than is necessary for temperature control, so that it must be heated again afterwards. Air conditioning wastes energy. It also wastes space, because air has to be pumped around in quite large tubes, so that it doesn't make a rushing noise. It does, nevertheless, generate a disturbing background noise if the room is otherwise quiet. There is worse news to come: air conditioning is spreading to more and more buildings in climates that we once thought were so mild that they would be immune.
Comfort involves more than cool air. Air conditioning also involves more than lowering the air temperature. It includes dehumidifying, cleaning (filtering), and circulating the air. Good air conditioning systems perform all of these functions, although most people focus on the "cool" concept.
Some Basic Facts About Your Home Air Conditioning System
