Car air conditioner working principle

The automobile air-conditioning refrigeration system is composed of a compressor, a condenser, a liquid storage dryer, an expansion valve, an evaporator, and a blower motor. The various components are connected by copper pipes (or aluminum pipes) and high-pressure rubber pipes to form a closed system. When the refrigeration system is working, the refrigerant circulates in this closed system in different states.

Each cycle has four basic processes: 1. Compression process: the auto ac compressor sucks the low-temperature and low-pressure refrigerant gas at the outlet of the evaporator and removes it. The gas compressed into high temperature and high pressure is discharged from the compressor. 2. Heat dissipation process: The superheated refrigerant gas of high temperature and high pressure enters the ac condenser. Due to the decrease of pressure and temperature, the refrigerant gas condenses into liquid and discharges a large amount of heat. 3. Throttle process: The refrigerant liquid with higher temperature and pressure becomes larger after passing through the expansion device, and the pressure and temperature drop sharply, and it is discharged from the expansion device in the form of mist (fine droplets). 4. Heat absorption process: The mist refrigerant liquid enters the evaporator core, so the boiling point of the refrigerant is much lower than the temperature in the evaporator, so the refrigerant liquid evaporates into a gas. In the evaporation process, a large amount of surrounding heat is absorbed, and then the low-temperature and low-pressure refrigerant vapor enters the compressor. The above process is repeated to achieve the purpose of reducing the air temperature around the evaporator.

The functions of automatic air-conditioning include automatic adjustment of temperature and humidity in the car, automatic control of return air and air supply modes, operation mode and air exchange volume control and other functions. The electronic control unit will make the air-conditioning system run automatically according to the settings made by the driver or passengers through the buttons on the air-conditioning display control panel, and adjust the air supply temperature and air speed in time according to the signals input by various sensors. Keep the air environment in the car at its best.


Post time: Jul-12-2021