Windscreen Demist Help
Key Tips for the winter season.
Quick tips to demist your windscreen
We’ve all been there; it’s a cold morning, you’re late, your windscreen is misted up and you’re tempted to drive off, with only a tiny gap of clear windscreen to see through. But don’t! Not only will it severely restrict your vision, making you more at risk of an accident, it could also be illegal. And anyway, you needn’t have to - by following a few simple steps you’ll be able to demist your windscreen in double quick time.
Why does your windscreen mist up?
On a cold, wet morning, the air inside your car is similar to the air outside. That’s all fine, until you get into the car. That’s when the warm, moist air from your breath meets the cold, moist air already in the car. The air from your lungs cools down, leaving the water vapour nowhere to go. So it condenses on the nearest and coldest surface, normally the windscreen. The result? You guessed it, a misty windscreen.
How to demist your windscreen?
1. Use the heater
Although you may be tempted to crank up the heater to maximum on an icy morning, all you’re doing is overloading the cabin with hot, wet air. Instead, start the heater on cold, then gradually increase the temperature as the air dries out. Also remember to direct your heaters onto the windscreen and windows – even on cold, this air will be warmer than the windows and will help to both dry out and heat up the glass to stop water vapour condensing on it again.
2. Use the air con (AC)
Contrary to popular belief, your AC system is not just for summer. Whilst it cools your car on a hot day by removing water vapour from the air inside the car, which in turn lowers the temperature of the air, the same principal applies in the winter too. Using your AC at the same time as the heater will remove water vapour on a cold morning, keeping the atmosphere inside the car dry, and preventing cooler air from condensing on the windscreen.
3. Use your climate control
If you have a climate control system, you may as well use it. Most systems will feature a special setting for demisting the windscreen – this will automatically adjust the parameters for the very best results.
4. Use your windows
Failing all that, and if you don’t have AC, you can resort to the good old fashioned method of winding down your windows. The air from outside can help to reduce the amount of water vapour inside the car, preventing the screen from misting up.
