Which air circulation mode should be used for defogging inside the car?
2 Answers
Using the air recirculation mode can defog the windshield faster. Here is a brief introduction to the recirculation and fresh air modes: 1. Recirculation mode: This mode is designed to prevent dust and odors from entering the car through the fresh air system by closing the external air intake duct, thereby blocking polluted outside air. 2. Fresh air mode: Since the car interior forms a relatively sealed environment, prolonged occupancy may lead to oxygen deprivation. Therefore, the air conditioning system includes an additional air duct to draw fresh air from outside, which then passes through the evaporator or heater core to deliver either cool or warm air.
When I encounter fogging inside the car, I always turn on the external circulation to defog first. Once while driving in the rain, the windows suddenly became foggy, almost obscuring the road. I quickly pressed the defog button on the center console—it usually has a fan-shaped icon. After activation, the car automatically switches to external circulation mode because the outside air is drier. Using internal circulation would trap moisture inside, making the fogging worse. The air conditioning also automatically dehumidifies, and both cold and warm air are effective. If there's no button, manually adjust the fan speed and temperature, then make sure the circulation mode is set to external. This is crucial for driving safety—address fogging immediately when visibility becomes blurry, don't delay. Regularly check if the air filter is clogged to keep the system running smoothly. This way, you can quickly handle fogging next time it happens.
