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What are the differences between vehicle air recirculation and fresh air mode?

4 Answers
MargaretFitz
07/28/25 10:24pm
The differences between vehicle air recirculation and fresh air mode are as follows: 1. Different working principles: Recirculation means the air inside the vehicle is heated or cooled and then recirculated back into the cabin; Fresh air mode draws outside air into the vehicle after heating or cooling it, achieving air exchange between the interior and exterior. 2. Different usage methods: When initially turning on AC cooling or heating, you can first activate recirculation to quickly lower or raise the cabin temperature; After temperature stabilizes, appropriately switch to fresh air mode for ventilation; Avoid using fresh air mode when outside air quality is poor, such as in heavy traffic with exhaust fumes or poorly ventilated underground parking. When driving on highways, never open windows - simply use fresh air mode instead. When outside air is clean but the cabin feels stuffy, promptly switch to fresh air mode for ventilation.
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MacJohnny
08/12/25 1:50am
The difference between the car's internal and external air circulation is simply the source of air. Having driven for years, I know that internal circulation recirculates the air inside the car. It's usually activated by pressing a button and is ideal for quick cooling or heating, like turning on the AC in summer and switching to internal circulation to prevent hot air from entering. External circulation draws in outside air, which is great for fresh air or defogging, such as using it on highways to avoid wind noise from open windows. I usually switch based on the situation: in city traffic jams, I use internal circulation to reduce exhaust fumes and prevent dizziness; in open outdoor areas, I switch to external circulation for fresh air. However, prolonged use of internal circulation can make the air stuffy and increase CO2 levels in the car, affecting concentration. That's why the car's AC system is well-designed and practical.
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BrookeLee
10/01/25 3:56am
The difference between the vehicle's internal and external air circulation is quite obvious. Having driven for decades, I can say that internal circulation keeps the air inside the car flowing in a loop without drawing in fresh air from outside. It's typically used when the air conditioning is on to quickly cool down or warm up the cabin. For example, in winter, turning on the heater with internal circulation warms up the car faster, but don't use it continuously as it can lead to poor air circulation and mold growth. External circulation, on the other hand, brings in outside air, which is beneficial for health. During long drives, switching to external circulation allows you to inhale fresh oxygen, reducing fatigue, and it also effectively clears fog from the windshield. I recommend using external circulation more frequently on highways or rural roads to ensure regular air exchange. In urban areas with frequent traffic lights, minimize external circulation to reduce exhaust fumes. Regularly cleaning the air conditioning filter is also crucial to prevent airflow blockage. This design is quite user-friendly.
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MacEmilio
11/14/25 5:44am
The difference between the vehicle's internal and external air circulation lies in the airflow path. As an automotive enthusiast, I know that internal circulation closes the external air intake, only recirculating the air inside the car, similar to closing all windows and doors while running a fan. External circulation opens the air intake, drawing in outside air, like cracking a window for ventilation. The air conditioning system uses computer-controlled dampers to achieve this. It's very user-friendly: internal circulation saves energy and cools faster when cooling is needed; during external circulation, if air quality is poor, sensors automatically adjust the fan speed. I've also installed a high-efficiency filter to enhance air purification. From my experience, internal circulation is ideal for rainy or smoggy days, while switching to external circulation on sunny highways provides a refreshing experience. The overall design ensures a comfortable driving experience.
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