Why does the car air conditioner blow hot air when AC is turned on?

[CarolineRose]

When the car air conditioner blows hot air with AC turned on, it is because the temperature is not adjusted to the cooling zone. Below is the relevant introduction about car air conditioning: 1. Compression process: The compressor inhales the low-temperature and low-pressure refrigerant gas at the outlet of the evaporator and compresses it into high-temperature and high-pressure gas, which is then discharged from the compressor. 2. Heat dissipation process: The high-temperature and high-pressure superheated refrigerant gas enters the condenser. Due to the decrease in pressure and temperature, the refrigerant gas condenses into a liquid and releases a large amount of heat. 3. Throttling process: The refrigerant liquid with higher temperature and pressure passes through the expansion device, causing its volume to increase, and the pressure and temperature drop sharply, discharging from the expansion device in a mist form (fine liquid droplets).