What does the car's internal circulation mean?

2 Answers
LaHeidi
07/24/25 1:43pm
Internal circulation means that the air can only circulate inside the car, driven by the blower to circulate the air inside the vehicle. Below is a relevant introduction about circulation: Concept: It uses a fan to draw air from outside the car into the interior, meaning the air passage between the outside and inside of the car is open. Precautions: Shortly after entering the car, you should open the windows or turn on the external circulation ventilation system to introduce fresh air. You should not drive for a long time with the windows and doors closed, nor should you sleep or rest for extended periods in a sealed car. After purchasing a new car, you should try to maintain air exchange between the inside and outside of the car as much as possible, similar to a newly renovated house, to allow harmful gases inside the car to volatilize and be released as soon as possible.
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McFrank
08/11/25 7:42am
I've been driving for fifteen years, on the road every day, and I'm very familiar with the recirculation function. Simply put, it means the air conditioning system doesn't draw fresh air from outside but instead recirculates and treats the air inside the car. In summer, when I get into a car that's as hot as a steamer, I immediately press the recirculation button. The fan can cool the car down quickly because it's processing the already cooled air inside, without having to fight the hot air outside. The same goes for heating in winter—it warms up just as fast. I often use it in traffic jams to reduce inhaling exhaust fumes, which helps prevent headaches. But don't keep it on all the time—the air can get stuffy, and the oxygen levels drop, making you dizzy after a while. I usually switch back to fresh air mode after half an hour to let in some fresh air. It also saves a bit of fuel and reduces engine load, especially useful in high-wind areas on highways. Remember, using it in heavily polluted or smoky areas can protect your health, but the key is to switch modes wisely.
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