How to turn on the air conditioner to prevent fogging on rainy days?
2 Answers
Spray anti-fog agent on the windows, so that when driving in the rain, the windows will not fog up, and the driver's vision will not be obstructed. When turning on the air conditioner, you can slightly open the windows to create a convective airflow, which can effectively remove fog and prevent the windows from fogging up.
Having driven for decades, I've seen countless instances of foggy windows on rainy days, primarily caused by high humidity from rain meeting cold glass. The most effective method I use for defogging with the AC is this: don't rush to drive off immediately after getting in the car. Start the engine and turn on the air conditioning system first, ensuring it's set to external circulation mode rather than internal, allowing fresh outside air to enter and reduce moisture buildup inside. Then press the defog button—usually depicted as a windshield with airflow—set the temperature higher, say above 25°C, and adjust the fan speed to medium or high, ensuring warm air blows directly onto the windshield. Why does it work? It removes interior moisture and heats the glass to balance the temperature difference, clearing the fog in minutes. Before any rainy drive, I always preemptively turn on the AC to defog before setting off—much safer and more reliable. As a side note, regularly cleaning the windows and replacing the AC filter can help prevent the issue.
