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Car windscreen misting up. Should I use hot or cold air?

In the cold mornings when the screen is misty, should I use the hot air or cold air on the air con thing to clear it?
Reply 1
Hot air probably evaporates the condensation a bit quicker than cold air, but as long as you've got the air con switched on it doesn't make a huge difference what temperature you use.
I find hot air is the one to go for... cold air does bugger all.
Put fog x on it.

I dont have a heater in either of my cars. They dont mist up.
Reply 4
If you're having a lot of issues with your car misting up check there isn't water getting in some how. If you're really lucky there might be quite a lot of water in one of the food wells, under the back seats or in the spare tyre well.
Reply 5
Original post by KCLeblanc
If you're really lucky there might be quite a lot of water in one of the food wells, under the back seats or in the spare tyre well.


Since when was this a good thing? :s-smilie:

Also check your pollen filter, because if it's badly clogged up with a load of crap it can restrict the airflow into the cabin and make demisting take much longer.
I find using A/C clears the screen quicker, but if you turn it off it mists straight back up, and on a cold morning you're probably not going to want the A/C cold air. Hot takes a little longer, but it stays clear and keeps you warm. An absorbent cloth helps things along on really damp mornings.
Reply 7
Original post by Runninground
In the cold mornings when the screen is misty, should I use the hot air or cold air on the air con thing to clear it?


Moderately hot air - cold air does very little, but if you turn it up to max you may find the air coming out is actually quite humid and tends to cause further condensation.

Also, if you do have actual Air Conditioning (there will be an AC button somewhere), turn that on - the reduced humidity in the incoming air makes a lot of difference, and prevents it from misting up again as it offsets the humidity from your breath.
Reply 8
Original post by Walter Ego
on a cold morning you're probably not going to want the A/C cold air.


You can run the air conditioning regardless of what temperature the heater/climate control is set at. You don't have to freeze to death. :wink:
Reply 9
hot but cold can also work
Reply 10
Hottest air so you warm the glass up.
Then wind the window down a bit so you don't sweat and make it worse.
Firstly make sure your windscreen is clean as they'll mist up less.

To demist set temperature to high and if you have A/C, put it on. :smile:
Reply 12
Hot air and drop the window half an inch.
Reply 13
Drop top. Wipe glass. Drive.
Reply 14
I normally leave it at between hot and cold plus the air conditioner switched on. Make sure outside air is coming in though and it isn't on recirculate mode.
Reply 15
I set the dial halfway between hot and cold then blast it, clears the mist in seconds.

I do find cold doesn't work as quickly.
Reply 16
Hot air obviously

This is year 9 science, moisture in the air condenses on cold surfaces which causes misting on the windscreen. Heating it up with some hot air will prevent this to ensure your windscreen stays clear.

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