How to Deal with Foggy Car Windows When Using Air Conditioning?
3 Answers
When the car windows fog up while using air conditioning, you can slightly open both side windows to allow air circulation. This helps eliminate the temperature difference on both sides of the windshield, making it difficult for fog to form. However, blowing cold air is a quick but temporary solution, while blowing hot air can fundamentally solve the issue of foggy windows. The principle of defogging spray is simple: spraying a layer on the windshield forms an effective protective film, preventing the condensation of water vapor.
Fogging on car windows when the air conditioning is on is quite common. This happens because the cold air from the AC meets the humid air, causing condensation. Having driven for many years, I immediately press the defog button (usually located on the AC control panel) when this occurs, turn the fan to maximum speed, and direct the airflow toward the windshield. If the effect isn’t noticeable, I switch to the external circulation mode to balance the humidity inside and outside the car. Sometimes, when the weather is particularly humid or rainy, the fogging worsens. In such cases, I try opening the windows for a minute or two to let the moisture dissipate before turning the AC back on. Prevention is key—make it a habit to check the AC settings before driving and avoid keeping damp items in the car. Safety comes first; foggy windows can obscure vision and lead to accidents, so stay focused and prioritize clearing the glass. I recommend keeping a defogging cloth in the car—it’s cheap and practical. During regular maintenance, have a technician check the AC filter, as a clogged one can worsen humidity issues.
When I first started driving, I was often troubled by fogged-up windows, especially when using the air conditioner on rainy days—everything would turn white. After asking friends, I learned it was due to high humidity inside the car. The solution is simple: turn on the air conditioner, select the defogging mode, increase the fan speed slightly, and set the temperature a bit higher than the outside to avoid a drastic temperature difference. Switching between recirculation and fresh air modes also helps—for example, first use the fresh air mode to draw in dry air, then switch to recirculation to maintain the temperature. Now I’ve learned to turn on the defogging mode and wait a minute or two before driving. Don’t ignore this issue; fogged-up windows seriously affect safety—I’ve nearly hit things a few times. By the way, if your windows frequently fog up, it might indicate an issue with the wipers or seals, so it’s best to get them checked at a repair shop. Also, drying the door edges during car washes can prevent moisture from seeping in—these small habits really save a lot of trouble.
