Traditional air conditioners, known as split-system or window air conditioners, do not use water as a primary component in the cooling process. Instead, they use a refrigerant, typically a chemical compound known as hydrofluorocarbon (HFC), to absorb heat from the indoor air and release it outside.
The basic working principle of an air conditioner involves the following steps:
Compression: The refrigerant is compressed into a high-pressure, high-temperature gas.
Condensation: The hot, pressurized gas is then passed through a condenser coil located in the outdoor unit of the air conditioner. As it loses heat to the outdoor air, it condenses into a high-pressure liquid.
Expansion: The high-pressure liquid refrigerant is passed through an expansion valve, where it undergoes a sudden drop in pressure. This causes the refrigerant to evaporate and turn into a low-pressure, low-temperature gas.
Evaporation: The cool gas is then passed through an evaporator coil located inside the indoor unit of the air conditioner. As it absorbs heat from the indoor air, the refrigerant evaporates and turns back into a low-pressure gas.
Air circulation: The indoor fan blows warm indoor air over the cold evaporator coil, cooling the air and removing moisture (humidity).
Repeat cycle: The refrigerant, now in a low-pressure gas state, returns to the compressor to start the cycle again.
The cooling process does cause some condensation to occur on the evaporator coil due to the removal of humidity from the indoor air, but this condensed water is typically collected in a pan or tray and drained away through a pipe, which is why air conditioners have a drain line.
However, there are specific types of air conditioners called "evaporative coolers" or "swamp coolers" that use water to cool the air. These are more commonly used in dry climates. Evaporative coolers work by drawing warm air through water-saturated pads, causing the water to evaporate and cool the air before it is circulated into the room. Unlike traditional air conditioners, evaporative coolers do not use refrigerants or compressors and are generally less effective in humid environments.