The compressor compresses the gaseous refrigerant into a high-temperature and high-pressure gaseous refrigerant, and then sends it to the condenser (outdoor unit) to dissipate heat and becomes a normal temperature and high-pressure liquid refrigerant, so the outdoor unit blows out hot air. Then it goes to the saving device and enters the evaporator (indoor unit). After the refrigerant reaches the evaporator from the throttling device, the space suddenly increases and the pressure decreases. The liquid refrigerant will vaporize and become a gaseous low-temperature refrigerant, thereby absorbing a large amount of The heat of the evaporator will become colder. The fan of the indoor unit blows the indoor air through the evaporator, so the indoor unit blows out cold wind; the water vapor in the air will condense when it meets the cold evaporator. Water droplets flow out along the water pipe, which is why the air conditioner will emit water. The gaseous refrigerant returns to the compressor to continue compression and continue to circulate.