What Are the Techniques for Defrosting and Defogging a Car?
3 Answers
For most car owners, using the air conditioning system to defog is a common method. Almost all cars on the market today have air vents located under the front windshield. Simply adjusting the air conditioning to the appropriate setting allows the airflow from the vents to clear the fog. Turning on the car's fan and the cooling switch will quickly dissipate the fog on the front windshield with cold air, which is very effective. However, this method has a drawback: the cold air can make passengers inside the car feel uncomfortably chilly, especially during the already cold winter months. Moreover, the fog may reappear once the cold air is turned off, making it not the most recommended method for defogging.
As a new driver, I used to panic when encountering window fogging. The first trick I learned was using warm air from the AC to defog: turn on the warm air immediately after starting the car, set it to windshield mode, and let the warm air blow gently. Meanwhile, crack open a window slightly to let dry outside air carry away the moisture. If there's a defog button, pressing it directly is even more convenient. In winter when there's frost, I need to preheat the car for a few minutes, then gently use the wipers or spray some defroster. Remember not to blast cold air directly, as it'll create more fog. New drivers tend to rush, but I've learned to patiently wait until the fog clears before driving to avoid accidents from poor visibility. These are practical skills not taught in driving school - safety first is what really matters. I've also tried anti-fog spray on the glass, which works well but requires choosing mild products to avoid damaging interior components. Normally, I also pay attention to preventing excessive humidity when parked by using desiccants to prevent fogging.
With 20-30 years of driving experience, I'm very familiar with defrosting and defogging. My old-school method is to check the windshield before getting in: if there's frost, I start the engine to warm up for a few minutes, then blast the heater to melt it. For fogging, I directly use the AC's dehumidification mode. If the outside air is dry, I switch to external air circulation to speed up the process. On rainy or cold foggy days, I leave earlier to warm up the car and stabilize the interior temperature before driving. Daily maintenance is also crucial: no wet clothes or umbrellas left inside, and cleaning the inner windows with a soft cloth to remove grease reduces fog buildup. I keep an electric defroster or anti-fog spray for emergencies – a quick spray does the trick. Experience tells me it's safest to drive only after the fog clears, never rush at the risk of safety. In winter, covering the windshield with a cloth prevents frost – economical and worry-free.
