How to Deal with Foggy Side Windows?

[CadenLee]

Press the defogging button, turn on the air conditioning cooling (A/C) switch, set the temperature to the lowest, and switch to external circulation to remove fog. Both cold and warm air can be used to defog car windows, but warm air is slower than cold air. The most effective method is using cold air, which blows dry cold air directly onto the glass, preventing water vapor from condensing on the glass and achieving defogging. The method for using warm air is the same as cold air, but note that warm air should not be used for defogging on rainy days as it may initially worsen the fog. Always use external circulation when defogging car windows. The reason for car window fogging: There is a certain temperature difference between the inside and outside of the car. If the temperatures inside and outside are different, the surface with the lower temperature will have a lower saturated vapor pressure than the surrounding environment, causing water vapor to gather on the glass surface and form tiny droplets, resulting in fog. Methods to defog car windows: Air Conditioning Cooling: Use the air conditioning's dehumidification function to reduce air humidity and remove fog. In summer, especially when multiple people enter the car and the air conditioning is not turned on promptly, the exhaled air has high humidity, quickly causing the windshield to fog up. In this case, turn on the air conditioning to blow cold air onto the windshield, using the dehumidification function to remove fog quickly. If the humidity is too high and the air conditioning is ineffective, slightly open the window to rapidly reduce the humidity inside the cabin. Combining this with the air conditioning can speed up the process. Air Conditioning Warm Air: Use the method of reducing the temperature difference to remove fog. In winter, blow warm air onto the glass to quickly raise the windshield temperature and reduce the temperature difference between the inside and outside surfaces, preventing heavy fogging. Note that the rear and side windows heat up more slowly, so it takes longer to remove all fog. Whether using automatic or manual air conditioning, turning it on helps with dehumidification. Avoid setting the temperature to the coldest position, as prolonged use can cause frost to form on the outer surface of the windshield. Applying Anti-Fog Agents for Prevention: Spray a small amount of defogging agent on the car windows and wipe it clean to remove dirt and stains. While polishing the glass, a thin transparent protective film forms, effectively preventing water vapor from condensing into fog, especially useful in cold winters. Alternatives to anti-fog agents include dish soap, soapy water, glycerin, alcohol, or saline solution. After applying, let it dry and then wipe off excess residue with a chamois or soft dry cloth to ensure the windows remain fog-free for several days. Opening Windows for Airflow: If the fog inside the car is not heavy, open both side windows to create airflow between the inside and outside, reducing the temperature difference and gradually dissipating the fog. This method works on the same principle as using cold air from the air conditioning. However, this method has obvious drawbacks and cannot be used during rain, snow, on highways, or when the fog is heavy. Rear Windshield Heating: Most cars have a rear windshield heating function, though the button location may vary. Turn on the windshield heating switch, and the fog on the rear windshield will disappear in about a minute.