They keep us cool, they provide happy sanctuary on summer days and, sometimes, they make a lot of noise. Air conditioners are a little big, a little clunky and a little inconvenient depending on the model, but they sure get the job done – though most people probably don’t have a clue how air conditioners work. This article will tell you just what’s going on inside that noisy contraption.
Though modern air conditioner models can fill several different roles at once, the average unit was, is, and probably always will be designed to cool down the air in an enclosed space. This can range from a house to an apartment to an office to a car: so long as the air conditioner is exposed to an area that has little access to the outdoors, it can bring the overall temperature down. This makes air conditioners important appliances during hot summer months where living is otherwise unbearable. But how do they do this?
At first glance, the air conditioner is doing just one thing: pumping out cold air. Sit in front of one and this is readily apparent. The air conditioner needs to take in air in order to do this, however, and consequently what’s actually happening inside these units is air cooling. The air conditioner takes in the hot air and pumps it back out as cold air.
The key to the air conditioner’s power lies in a refrigerant known as freon. Freon begins life in the air conditioner as a cool gas that, when the machine is started up, is filtered down into a component known as the compressor. The compressor takes in the freon and applies massive amounts of pressure, and in doing so significantly heats the freon.
The freon is then passed through the air conditioner’s condenser coils, which are found outside the guts of the air conditioner. As the freon passes through the coils it gives off heat which rises to the top of the room, and by the end of the trip the freon is a liquid under high pressure rather than a gas.
Once the freon is a liquid it drips into a third component known as the evaporator. Once inside the pressure is released and the freon rapidly turns back into a gas. It then begins to interact with the hot air that was being pulled into the air conditioner, sucking the heat out of the air. The freon is sent back to the condenser as a cool, low-pressure gas to begin the process over again, while the cold air is pumped back into the enclosed place via fans. This creates the cold breeze so often associated with air conditioning units.
Depending on the unit, there’s also typically one more step in this process: a thermometer. In HVAC units in particular the air conditioner takes constant readings of the temperature of the enclosed space, and once that temperature hits a certain point the air conditioner shuts down automatically. It will also turn back on if the temperature rises.
This, of course, only covers the basics of air conditioning systems. More complex units – say, an air conditioning system for an entire building – will have multiple cooling boxes connected to a single thermometer, and will run the cool air through ducts to reach remote portions of a space. That said, however, most air conditioners still follow the same general principals.
