How to Solve Fogging on Car Windows When Using Air Conditioning in Summer?
3 Answers
There are two main reasons for fogging on car windows when using air conditioning in summer: 1. High humidity and low interior temperature. 2. High humidity: When the humidity in the air is constant, if the temperature of the car window is lower than the dew point, fogging will occur on the car glass. 3. Low interior temperature: When there is a certain temperature difference between the inside and outside of the car, moisture will gather on the car glass and condense into fog. Here are some solutions to address fogging on the windows: (1) Wipe it clean yourself: Many car owners keep a small cloth in their cars, which is the most direct method. However, the effect of wiping is not ideal, and it is only a temporary solution, not very convenient. (2) Use specialized anti-fog products: Before driving, evenly spray the anti-fog agent on the surface of the car window glass, then wipe it clean with a dry towel. The principle is to form a protective film on the window surface, altering the surface tension of water molecules to prevent moisture from condensing on the glass, thus avoiding fog formation. One application is effective for about 10 days. (3) Open the window slightly: Opening the window can appropriately increase the interior temperature and reduce the temperature difference between the inside and outside of the car, effectively solving the fogging issue. Of course, high-end cars come with temperature adjustment features; simply adjusting the interior temperature slightly higher will suffice.
It's common for car windows to fog up when I use the air conditioning in summer, mainly because the outside temperature is high on hot days, and the cold air from the AC makes the glass too cold, creating a large temperature difference between the inside and outside of the car, which leads to condensation. This issue isn't too hard to handle. I usually start by pressing the defog button on the dashboard, which typically has a fan icon pointing toward the front window symbol. When activated, the AC automatically increases airflow and temperature to clear the fog. Sometimes, I directly lower the AC temperature setting and adjust the air vents to blow toward the windshield, as the cold air can quickly disperse the fog. If the fog is heavy, I also crack open a window slightly to balance the airflow inside and outside the car, preventing obscured visibility while driving. For regular maintenance, I check if the AC filter is clean and replace it periodically if dirty, as a clogged filter can reduce defogging effectiveness. Additionally, I avoid setting the temperature difference between inside and outside the car too extreme, keeping it within a comfortable range. In short, after a few tries, you’ll find the right trick that works for your car.
Window fogging in summer when the AC is on can indeed be quite annoying. My approach mainly combines the use of AC functions and daily habits. When fog appears, I immediately turn on the defogging mode, which automatically adjusts airflow and temperature to resolve the issue. I set the fan speed higher, like blasting it at maximum for a few minutes, and the fog clears quickly. Then I reduce it to medium speed. For temperature, I set it slightly higher to avoid excessive cold, which can worsen fogging due to temperature differences. I also frequently use the external circulation mode to let outside air dilute the humidity inside. In the long term, I clean the car's corners before the rainy season to prevent mold odors from increasing humidity. When parked, I don’t leave the windows completely closed, allowing the car to ventilate. For safety, I slow down or pull over as soon as fog appears, ensuring clear visibility before continuing. These small actions are simple but effective, making your drive more reassuring.