How to Use the Defog Button in a Car?
2 Answers
The method to use the defog button in a car is: 1. Turn on the window defogging mode; 2. Open the windows to allow air convection, balancing the temperature inside and outside the car; 3. Spray defogging agent on the glass; 4. Turn on the car's warm or cool air to blow on the glass. The reasons for window fogging are: 1. When humidity is high, the window temperature is lower than the dew point temperature; 2. When the temperature is too low, the surface moisture on the window becomes saturated, and the vapor pressure is lower than the surrounding environment's vapor pressure; 3. There is a certain temperature difference between the two sides of the window; 4. There is a significant temperature difference between the inside and outside of the car; 5. The car floor mats are damp. The letter for the front windshield defog is FRONT, and the letter for the rear windshield defog is REAR.
That day I was driving when the rain and fog completely covered the front windshield. I quickly found the defogger button with a fan and wavy lines and pressed it. The car immediately roared loudly, with the vents blowing cold air directly onto the glass. In less than two minutes, the fog was completely gone. The rear window defogger button has a square icon—pressing it activates the heating wires on the rear window. I’ve tried using warm air in winter, but it makes the fog worse. In that case, you must turn on the A/C button along with the defogger, or else the humidity won’t dissipate. Remember to press it as soon as the fog starts forming; waiting until visibility is completely blurred is dangerous, especially on the highway. During defogging, the AC automatically switches to external circulation, which works much better than internal circulation.
