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What is the reason for fogging up the windshield of a car in winter?

What is the reason for fogging up the windshield of a car in winter?

Most of us have faced the problem of fogging up car’s windshield and windows especially in winter. It is not only inconvenient and irritating when we want to drive, but also can be very dangerous. Here in this article we will give you some tips to prevent or deal with fog inside of your car.

At first, let’s have some insight into why windshield fogs up. It happens because the temperature outside is colder than inside the car. And when we start inhaling cold air and exhaling warm air, the cold air meets warm and moist air making windows to be covered by fog.

Let’s now turn to our quick guide on our defogging tips if you have been stuck in this situation at least once in your life.

Setting the heating and ventilation system

  1. In order to get rid of fog, the best option is turning on the air conditioning system (A/C). This way you’ll take the condensation out of the air. Though it is preferred to run the A/C on cold, but you can slowly increase the temperature if it’s becoming quite cold inside.
  2. You can also evaporate water vapor with the help of defrosters of your car. Just turn the heat on and run it through them.
  3. Do not use car’s recirculation mode. In this mode the air is recirculated inside, so if the air is moist and damp, you won’t get any result. What you need is to get rid of moisture, not make it recirculate.

Other tips to prevent fogging up

Here are some other tips for preventing or dealing with fogging up problem.

  1. For a quick and easy fix, use a dry cloth (or a demister pad) and then, turn on air conditioning system.
  2. Always have air freshener in your car. It can be quite useful in case of fogging.
  3. There are anti fog coating products, sprays, defogger sponges etc. which can be easily bought from online or specialized shops.
  4. Open the windows to let the fresh air in and out the moist. This method can be applied if it is not so cold and there is no rain outside.
  5. In order to prevent windshield and windows from fogging up, clean them regularly. Dust and dirt create good preconditions for water molecules to stay on.
  6. Use car dehumidifier. It is a small sponge-like product, which absorbs moisture preventing the condensation process inside the car.
  7. Check if the seals of the windows and doors of the car are damaged. The seals keep the moisture out of the vehicle, and if they are damaged it will let the water in, causing humidity inside.

Hereby, in this article we tried to give you the main reasons of fogging up the windows and help you prevent or deal with this situation. Anyway, if the problem still exists or occurs frequently, we highly recommend you visiting your mechanic. It can be a problem of air flow, malfunction or damage of air conditioning system (A/C) or defrosters and so on.

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