Internal circulation is mostly used for traffic jams, and external circulation is mostly used for high speed. The use of internal and external circulation should be combined with air conditioning and warm air.

External circulation: the function of external circulation is well understood, that is, the air outside the car is sucked into the car by the fan. At this time, the air inside and outside the car can circulate with each other. Even if the fan is not turned on, the fresh air outside the car can still be replenished into the car.

Internal circulation: Contrary to the function of external circulation, the internal circulation of a car actually isolates the air inside and outside the car, which can be used to prevent dirty air from entering the car and dust and harmful gases from entering the car.

With external circulation, you can breathe fresh air outside the car. When driving at high speed, after a long time, the air inside the car will feel turbid, people will feel uncomfortable and the window will not open. External circulation should be used to ignite the breeze. It is too hot in winter to feel the warmth of the air. Turning on the external circulation can not only keep the temperature inside the car, but also freshen the air and make you feel more comfortable.

In hot weather, the air conditioner is used for internal circulation, and the air is adjusted by the air conditioner after intake, which can improve the working efficiency of the air conditioner and prevent polluting gases from entering the car. Million car purchase subsidy