Should You Use Cold or Hot Air to Defog Car Windows on Rainy Days?

[MaximusAnn]

Using cold air is more effective because when the outside temperature is higher or lower than the inside temperature, moisture will form on the windows. Alternatively, you can also open the windows to make the fog disappear. Here are the correct methods to remove fog from the windows: 1. Use the air conditioning cold air to defog: The most effective way to deal with foggy windows is to turn on the air conditioning (A/C) cooling, activate the external circulation, set the air direction to blow towards the windshield, and adjust to the maximum wind speed. 2. The dry cold air will blow directly onto the windshield, creating a 'air film' on the surface that prevents water vapor from condensing on the glass.