Should the car air conditioning be set to internal or external circulation?
2 Answers
Whether to use internal or external circulation for car air conditioning depends on the situation. Use internal circulation for short trips and external circulation for long trips. Internal and external circulation in cars refer to: 1. Internal circulation: Internal circulation means the air conditioning system is closed to external air and only recirculates the air inside the car. 2. External circulation: External circulation means the car air conditioning system is open to external air and draws in outside air for circulation. Car air conditioning generally includes cooling devices, heating devices, and ventilation devices. This combined system makes full use of the limited space inside the car, has a simple structure, and is easy to operate, making it the internationally popular modern car air conditioning system.
Whether to use the car air conditioner in recirculation mode or fresh air mode depends on your specific driving situation. Having driven for many years, I find that recirculation mode, which circulates the air inside the car, is suitable when the outside air quality is poor, such as during smog or traffic jams. It can cool down or warm up the cabin faster and prevent external odors from entering. However, prolonged use of recirculation mode can make the air inside stale, potentially causing drowsiness or dizziness. Therefore, I usually switch to fresh air mode after 10-20 minutes to let in fresh air, especially during highway driving, as it helps prevent window fogging and improves driving safety. In winter, using fresh air mode more often with the heater helps maintain humidity. Normally, you can combine both modes—for example, using recirculation mode initially for rapid cooling, then switching to fresh air mode for comfort.
