What are the differences between the internal and external circulation of a car's air conditioning system?
2 Answers
1. Internal circulation closes the airflow channel between the inside and outside of the car. Without the fan, there is no airflow circulation; when the fan is turned on, the airflow is drawn only from inside the car, forming an internal airflow cycle. External circulation uses the fan to draw air from outside the car, with the fan's output coming from the external environment. Even without the fan, airflow still enters the car while driving. 2. Internal circulation can effectively block external dust and harmful gases from entering the car and also helps maintain temperature. External circulation allows for breathing fresh air from outside. 3. In situations like heavy traffic in cities, tunnels, or dusty road conditions, we generally choose internal circulation. During long highway drives, if the air inside the car feels stale, external circulation should be used. Now, do you understand the differences between the internal and external circulation of a car's air conditioning system?
I've been driving for over ten years and noticed a significant difference between the recirculation and fresh air modes. The recirculation mode closes the windows and circulates the air inside the car without drawing in outside air, which is especially useful in traffic jams—it blocks exhaust fumes and dust while cooling or heating the car quickly. But be careful not to use it for too long, as the air can get stuffy and make you feel uncomfortable. The fresh air mode draws in outside air, which is great for long drives or areas with clean air, preventing window fogging or unpleasant odors inside the car. I remember one summer when I was driving on the highway with the fresh air mode on—the mountain air was incredibly refreshing, and with the sunroof open, I felt much more energized. In the city, I usually start with recirculation to cool the car down quickly, then switch to fresh air after about five minutes to keep the air fresh. It’s a comfortable and safe approach—I’d recommend giving it a try.
