Although there is a wide range in size and design, all air conditioners function in a similar fundamental way. Rather than just adding cool air to a room, an air conditioner actively removes heat and humidity from the air. It returns chilled air to the interior while transferring undesired heat and humidity outside. Common cooling systems include a compressor, a condenser coil, and an evaporator coil, as well as a specific chemical known as refrigerant. These components work together to transform the refrigerant from gas to liquid and back again efficiently. 

The refrigerant gas is compressed and heated before being sent to the condenser coil, which condenses back into a liquid. After that, the refrigerant goes back inside and into the evaporator coil. The indoor coil is then cooled by evaporation of the liquid refrigerant. A fan draws interior air through a cool evaporator coil, where the heat from the house is transported to the refrigerant. Once the air has been cooled, it is distributed throughout the house while the evaporated gas is rerouted outside to the compressor. When the refrigerant changes back to a liquid, the heat is dissipated into the surrounding air. Up until the required temperature is attained in your house, this cycle is repeated.