Understanding How Air Conditioners Work

Air conditioners work on fundamentally the same principles as kitchen refrigerators, only that with an air conditioner there is no box in place. Contrary to popular belief, air conditioners do not add cool air to the space; instead they draw heat away from the space or room. As a result, you will have a room that has significantly less heat, thus making it feel much cooler.

These units have a special chemical known as a refrigerant, which have the distinctive ability to change from gas to liquid in a very short period of time. Most systems today utilize a refrigerant known as Freon. This chemical compound is pumped into the unit during the manufacturing process, alongside some small amounts of lubricant for the compressor, a very important component of the air conditioning process.

All components of a typical unit form a closed system made up of a compressor, air condenser, thermostat, and an expansion valve. There are motorized fans also, whose main function is to spread the conditioned air, and the presence of thin metal fins facilitates rapid heat dispersion. The heaviest and probably the most important component of air conditioners is the compressor, because it should be strong enough to hold up a significant amount of pressure.

With that being said, the process of air conditioning starts with the refrigerant (in form of a cool gas) going into the compressor. As the gas finds its way into the inner chambers of the compressor, the compressor squeezes the cool gas to become very hot and highly pressurized.

This hot gas will go through condensing coils placed outdoors and the heat will dissipate into outside air, the same way the radiator of the car will dissipate heat from the coolant. Once the refrigerant goes through all the condensing coils, it will end up being a much cooler and will change from gas to liquid form.  

The liquid will still be under very high pressure and will be forced through a very small opening known as an expansion valve. The refrigerant in liquid form will now be coming out from the other end of the valve in very tiny amounts at a time. Since the rate of evaporation of the refrigerant is lower than that of water, it will start to evaporate as it travels through a new set of coils.

It is the process of evaporation that draws heat from the surrounding air, including air in the room. The fans will then blow across the metal fans placed on the coils, thus causing the cooling sensation in the room.

At this juncture, the liquid refrigerant would have been changed into cold gas again, and will find its way back into the compressor, and the process will start again until the thermostat registers a set temperature and shuts down the compressor.

Should there be a change in the temperatures again, the thermostat will sense the changes and will trigger the compressor to create more of the high pressured gas and the process will start all over again.