How to Use the Car's Internal Circulation?
2 Answers
Generally, when turning on the air conditioning for cooling or heating, you can first activate the internal circulation. Below is a partial introduction to internal and external circulation: 1. Principle of External Circulation: After the car's external circulation is turned on, the car's fan delivers outside air into the car, allowing air from outside and inside the car to circulate. Even if the car's fan is not turned on, gas will still enter the car while driving, providing external air to the interior. Even when the car's air conditioning is turned off while driving, air flow is still drawn into the car because the car is set to external circulation. If the car is driven in the city, turning on the external circulation will fill the car with exhaust fumes. 2. Principle of Internal Circulation: After the car's internal circulation is turned on, it indicates that the airflow channel between the inside and outside of the car is closed. If the car's fan is not working, there will be no airflow circulating inside the car. When the fan is working, the air it draws comes from inside the car, so the airflow inside the car keeps circulating. After turning on the internal circulation, it can effectively prevent external dust and harmful gases from entering the car, reducing the harm of external gases to the human body. For example, when driving through areas with smoke, dust, odors, or in heavy traffic, it can block some harmful gases. In general, if the external environmental quality is poor, it is necessary to press the internal circulation button inside the car.
I've been driving for decades and frequently use the recirculation function in my car. Typically, there's a button on the AC panel labeled "recirculation" or with a similar cabin icon—just press it to light up the indicator, and the air will circulate inside the car without drawing in outside air. The benefits are numerous: for example, in summer or winter, turning on recirculation helps cool or heat the cabin faster and more efficiently; it blocks dust, pollen, or heavy pollution from entering; and in traffic jams, it reduces exhaust fumes, making it healthier. I recommend not keeping it on continuously—switch to fresh air mode for ventilation after 10-20 minutes, otherwise, the air can become stale and cause drowsiness. It’s most useful during long drives in tunnels or rainy weather. For daily use, pairing it with automatic AC is more convenient, as the system balances internal and external airflow automatically. Remember, it’s a simple operation with significant effects—protecting the cabin environment and ensuring a more comfortable drive.
