Air conditioners are very important in countries with very high temperatures because they keep interior rooms cool.
- Air conditioners usually consist of two main parts. The indoor unit (by which the room is cooled or heated) and the outdoor unit (where there is a large rotating fan).
- The warm air from the room is sucked in through a grille located on the perimeter of the indoor unit (usually at the base or at the top). Subsequently, the air flows into pipes through which a coolant fluid circulates. This part of the machine works just like the refrigerator. It cools the incoming air and a dehumidifier removes any excess moisture.
- The air then flows over a heating element. On a cold day, this section of the unit can be turned up so that air conditioning works as heater. A fan blasts the air behind another grille in the room. If the heating element is pointed downwards, the air that re-enters the room is much cooler and the room is gradually cooled.
- Meanwhile, coolant (a volatile liquid that evaporates easily) flows through the chiller pipes, which are also in the indoor unit. As it flows, it gets heat from the air that blowing past the pipes and evaporates, turning from a cool liquid into a hotter gas. Subsequently, it transfers this heat from the inside of the room to the outside of the building, where the heat is pumped into the outside air.
- Just as in a refrigerator, the coolant flows through a compressor unit and a few condensing tubes, which turn it back into a cool liquid ready to repeat the same process again.
- In the unit outside the building (outdoor unit), there are many metal plates that dissipate heat in the atmosphere. An electric fan blows the air past them to speed up the process. So, as the time passes, the heat inside the building is gradually pumped into the outside air.