What does an air conditioner do?

An air conditioner is a device designed to remove heat and humidity from the air inside a room or space. It works by circulating refrigerant, a chemical compound that changes state between liquid and gas, in a closed system. The refrigerant is pumped through a compressor, which increases its pressure and temperature, causing it to turn into hot, high-pressure gas. This gas then flows through a condenser, where it releases heat to the outside air and condenses back into a high-pressure liquid. The liquid refrigerant then passes through an expansion valve, which reduces its pressure and temperature, causing it to vaporize and turn back into a low-pressure gas. Finally, the low-pressure gas flows through an evaporator, where it absorbs heat from the air inside the room and evaporates into a low-pressure gas. This process repeats continuously, removing heat from the air inside the room and transferring it to the outside air.