# How To Stop Car Windows From Steaming Up



## RandomlySet (Jul 10, 2007)

Recorded this over the weekend, you might be surprised with some of the results.

I tested the following:
Rain-X Anti Fog
Car Wax
Toothpaste
Bar of Soap
Shaving Get
Hand Sanitizer


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## boost monster (Jul 19, 2013)

I just leave my air con on all the time.


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## James_R (Jun 28, 2007)

Good video

The RainX Anti-fog seems to do the trick.
Thanks for sharing


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## Summit Detailing (Oct 9, 2006)

Unless it's a classic car just have the A/C on all the time as above^


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## RandomlySet (Jul 10, 2007)

Yes, I use AC too, but sometimes the window is almost dripping wet.... This was more about preventing it to begin with, rather than removing it afterwards.


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## Cookies (Dec 10, 2008)

My wife's cousin does a bit of rallying, and his rally Starlet steams up a lot. In the rallying fraternity, Head and Shoulders is widely recognised as preventing misting. It has to be genuine Head and Shoulders though. They guys have tried many other anti dandruff shampoos (I kid you not) and it turns out none of them were as good as the original. 

Great test. Must get a bottle of rain x (Or shaving foam....)

Cooks 

Sent from my SM-G950F using Tapatalk


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## RandomlySet (Jul 10, 2007)

Really!? Not heard that one.. A few people have mentioned Fairy Liquid - my mates fella and my dad. Both said they use(d) it inside their helmets


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## MBRuss (Apr 29, 2011)

Cookies said:


> My wife's cousin does a bit of rallying, and his rally Starlet steams up a lot. In the rallying fraternity, Head and Shoulders is widely recognised as preventing misting. It has to be genuine Head and Shoulders though. They guys have tried many other anti dandruff shampoos (I kid you not) and it turns out none of them were as good as the original.
> 
> Great test. Must get a bottle of rain x (Or shaving foam....)
> 
> ...


So what you're saying is that it's "head and shoulders" above the other anti-dandruff shampoos? 

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## Cookies (Dec 10, 2008)

MBRuss said:


> So what you're saying is that it's "head and shoulders" above the other anti-dandruff shampoos?
> 
> Sent from my LYA-L09 using Tapatalk


Yes, 8 out of 10 bald rally drivers (who expressed a preference) said their cats preferred it lol.

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## derbigofast (Dec 6, 2011)

no one has mentioned change the pollen filter as if its not bone dry there will be mass condensation in the car and for between £5 and £30 it is a relatively cheap alternative compared to some as the more moisture on windscreens runs water down behind the dash which is full of electrics and as we all know water and electrics go together like a house on fire


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## andy__d (Jun 27, 2018)

Hot moist air causes it mainly,, so tell the misses to shut up or open the windows,,,,
or dont make a coffee in the car,,,, 
Big Q is how many rolls of blue did it take to get the toothpaste & soap off,,,


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## RandomlySet (Jul 10, 2007)

derbigofast said:


> no one has mentioned change the pollen filter as if its not bone dry there will be mass condensation in the car and for between £5 and £30 it is a relatively cheap alternative compared to some as the more moisture on windscreens runs water down behind the dash which is full of electrics and as we all know water and electrics go together like a house on fire


My car isn't even a year old and has just over 3k miles.


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## RandomlySet (Jul 10, 2007)

andy__d said:


> Hot moist air causes it mainly,, so tell the misses to shut up or open the windows,,,,
> or dont make a coffee in the car,,,,
> Big Q is how many rolls of blue did it take to get the toothpaste & soap off,,,


A used a fair bit tbh.... Was a fricking nightmare


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## uruk hai (Apr 5, 2009)

Many years ago I used Rain X anti fog and for a short time it was impressive but one night I got in the car to come home and there were huge droplets of condensation inside the screen. It was so bad that I had to put a rolled towel at the bottom of the screen to stop it running behind the dash, I tried it on one more occasion with the same result and it went straight in the bin, now I just use a Pingi dehumidifier and it works a treat,


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## RandomlySet (Jul 10, 2007)

I'm wondering if I have a lot of condensation because I leave a bottle of QD in the rear door pocket....

I remember thinking with the Leon that the level in the bottle was going down quicker than I was actually ever using it... Do you think that could be a cause? I did remove the bottle a couple of weeks ago, but I imagine all the moisture that may have come from that is still in the car.


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## Andyblue (Jun 20, 2017)

RandomlySet said:


> I'm wondering if I have a lot of condensation because I leave a bottle of QD in the rear door pocket....
> 
> I remember thinking with the Leon that the level in the bottle was going down quicker than I was actually ever using it... Do you think that could be a cause? I did remove the bottle a couple of weeks ago, but I imagine all the moisture that may have come from that is still in the car.


If it's sealed / not leaking, then wouldn't have thought this would cause you issues.

If it's going down without you using it, then suggests it's leaking, so def worth looking at.


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## Andyblue (Jun 20, 2017)

RandomlySet said:


> Yes, I use AC too, but sometimes the window is almost dripping wet.... This was more about preventing it to begin with, rather than removing it afterwards.


Have you double checked you've not got a leak anywhere mate - really wouldn't have thought you'd have that much moisture in your new motor ...


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## RandomlySet (Jul 10, 2007)

No leaks that I can see, and no noticeable moisture anywhere (other than the windscreen :lol


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## Derekh929 (Aug 28, 2011)

Just take the wife the next time that will stop any problem with steaming windows job done:thumb:


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## andy__d (Jun 27, 2018)

similar with rainx anti fog BUT many years ago, they May have changed it by now
, still not going to touch it as there rainx water coating caused a brand new visor to become brittle 

Dont think ill try the toothpaste/soaps,, 


if your car is dripping screen, do sit in it and get Someone to play the hose over the car for a while to check for leaks, a mis-seated seal can happen, and while it is very uncommon, there have been a few brands with leaking brand new motors (volvo v50 top edge of windscreen for one, only on one model year but over All the engine/trim levels)


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## SadlyDistracted (Jan 18, 2013)

Summit Detailing said:


> Unless it's a classic car just have the A/C on all the time as above^


Just sounds like your cars got a leak and there is consequential damp in there.

I had a 5 series that had window misting problems - turned out that on rh drive cars theres a large plastic blanking piece where the steering colum goes on lh drive cars, and if the car was parked the wrong way on an incline water would seep in then collect under the floor soundproofing. Was a ***** to get the car dried out and the blank sealed - after this never had a problem!


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## andyymurphyy (Nov 25, 2018)

RandomlySet said:


> I'm wondering if I have a lot of condensation because I leave a bottle of QD in the rear door pocket....
> 
> I remember thinking with the Leon that the level in the bottle was going down quicker than I was actually ever using it... Do you think that could be a cause? I did remove the bottle a couple of weeks ago, but I imagine all the moisture that may have come from that is still in the car.


I had this issue on a 2012 Ford Focus when the front passenger door seal started to come away along the bottom sill. Practically every mk3 Focus I saw thereafter had the same issue where a rubber seal could be visible from the outside.

It does sound like a leak of some description...

Andy

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## Demented (Nov 3, 2014)

Have you ensured the AC is not on recirculate.

When the AC is on its recirculate setting, even with the AC off; the air/atmosphere within the interior is being recirculated and if the blower is set to clear the windscreen, this recirculated air, which contains either warm moisture from breathing, talking or dampness from clothing, is forced onto the cold glass.

With the AC on; the recirculate setting should only be ON when the outside temperature is hot.

The idea is to continuously recirculate the cold interior air/atmosphere, which has already been cooled by the AC and to prevent the hot outside temperature from entering the interior.


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## RandomlySet (Jul 10, 2007)

Yes, it's not on recirc - I pretty much never use recirc TBH.


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## Cookies (Dec 10, 2008)

Have a feel of the carpets, mate. Lift out the mats, and see if there's any dampness underneath. If you can, try lifting the carpets a bit and see if you can get your hand underneath to the sound proofing foam and see if there's any moisture there. 

Perhaps get a wee dehumidifier into the car for an evening, to dry it out. Then see how quickly the condensation reappears. It might be that the car just isn't getting warm enough with such little use. 

Cooks

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## Sh1ner (May 19, 2012)

Recirc is the best and fastest way to clear the screen and warm the air in the cabin quickly. Warm air can hold more moisture than cold. Recirc can be used for faster heating as well as cooling.
The recirculated air will still be passing over the evaporator and heater matrix allowing it to dry and warm faster which is better than introducing more cold damp air. Although it will dry a little as it passes over the evaporator.
The problem is the cold screen. Once that is warm enough then there is no condensation.
It might be worth checking that ac and if fitted sunroof drains are clear and any water that is collecting on the evaporator is draining out and not remaining in the heater.
We have a smoke machine that fills the car and any leaks around door seals light fittings, sunroof etc can be sniffed or seen.
Damp carpets are an easy giveaway but you often need to lift and check underneath because water can sit in the backing and not be felt on top.

It should not really be happening on a new vehicle and I would give it back and let them sort it.


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## Demented (Nov 3, 2014)

Sh1ner said:


> Recirc is the best and fastest way to clear the screen and warm the air in the cabin quickly. Warm air can hold more moisture than cold. Recirc can be used for faster heating as well as cooling.
> The recirculated air will still be passing over the evaporator and heater matrix allowing it to dry and warm faster which is better than introducing more cold damp air. Although it will dry a little as it passes over the evaporator.
> The problem is the cold screen. Once that is warm enough then there is no condensation.
> It might be worth checking that ac and if fitted sunroof drains are clear and any water that is collecting on the evaporator is draining out and not remaining in the heater.
> ...


www.worldclassautoservice.com/use-cars-recirculation-button/


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## Tykebike (Mar 27, 2016)

(volvo v50 top edge of windscreen for one, only on one model year but over All the engine/trim levels)
My wife's second hand V50 had this problem and thankfully the dealer (Ray Chapman York) honoured the comprehensive warranty and sorted it for us.


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## andy__d (Jun 27, 2018)

Tykebike said:


> (volvo v50 top edge of windscreen for one, only on one model year but over All the engine/trim levels)
> My wife's second hand V50 had this problem and thankfully the dealer (Ray Chapman York) honoured the comprehensive warranty and sorted it for us.


hate to burst your bubble, but it was a Recall by volvo (TSB) that should have already happened, as as its volvo the recalls stay valid until applied to the car.

to be valid , for the windscreen issue, all that is needed is that it is the Gen volvo screen.


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## Sh1ner (May 19, 2012)

Demented said:


> www.worldclassautoservice.com/use-cars-recirculation-button/


If you are happy to believe that is the best way then fine. Having worked on automotive air conditioning systems for over 40 years I'll stick with what I know.
Air con systems do not switch on, from cold, until the system is at a minimum temperature, so temperature stability can be maintained. All you are doing is putting in more cold moist air and cooling the cabin further because the heater core is not actually hot and is being further cooled by cold air.
On recirc the air is still being dried by the evaporator as well as heating the matrix and everything warms up faster.

Older R12 (Freon) very cold but environmentally unsound and many R134a systems did not have a recirc button and relied on air being forced over the evaporator which condensed some of the water vapour so less damp air was let into the cabin. There is an advantage to having the aircon on but older systems could run much colder, ice coming from the vents with R12, which is not possible with modern systems hence the introduction of the recirc button which allows an inferior system not only seemingly better cooling but also heating by reusing air that has been heated just as it would, had it been cooled.

I would agree that fresh air is nicer than recirculated but it will warm the screen faster on recirc than fresh.


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## footfistart (Dec 2, 2013)

I’ve used carpro fog fight which is amazing but can be a bit of a pain to apply and not get it to smear as it’s one of those coatings you can’t touch after it’s applied 


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## Demented (Nov 3, 2014)

Sh1ner said:


> If you are happy to believe that is the best way then fine. Having worked on automotive air conditioning systems for over 40 years I'll stick with what I know.
> Air con systems do not switch on, from cold, until the system is at a minimum temperature, so temperature stability can be maintained. All you are doing is putting in more cold moist air and cooling the cabin further because the heater core is not actually hot and is being further cooled by cold air.
> On recirc the air is still being dried by the evaporator as well as heating the matrix and everything warms up faster.
> 
> ...


It's not what I believe it's what I see with my own eyes.

It's like a bathroom mirror, it mist up because the hot water emits a vapour and the glass mirror is cold or at least of a lower temperature than the vapour, when this vapour makes contact with the cold mirror, the mirror mist up; of which I can prevent by opening my bathroom window slightly and the fresh air from outside entering the bathroom clears the mirror.

I got my first car with AC roughly 30 years ago and my first winter with that car, with the AC off, I experienced the excessive condensation occuring; even whilst driving with the heater on, interior nice and warm, windows completely clear and within seconds of outside weather conditions becoming overcast and the slightest of rain, the windows would completely mist up.

Initially, I thought like everyone else, dampness within the car; I asked around and everyone came to same conclusion, either dampness, sunroof drainage, doors seals etc and all was checked and nothing was found to be at fault or allowing water into the car.

I persevered with this until one day, the penny finally dropped; during an overcast winters day with all the windows misted up and the AC off; I noticed the heater fan blower was on the Recirculate setting and the moment I turned it off Recirculate to its normal blower setting, the windows cleared almost instantly.

At the time, I had no idea what the AC Recirculate setting meant; the dial didn't actually state Recirculate, just displayed a rotating arrow type image.

Since, I've owned many cars with AC and the only time the windows have misted up excessively is when someone has changed the AC settings to Recirculate and I didn't notice until the windows mist up.

Now, unless it's a hot summers day and with the AC on; I ensure the Recirculate setting is off.


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## Alex_225 (Feb 7, 2008)

I used to use the AC to clear the windows of my car. But it got to a point it would steam up every time it was remotely cold or damp outside. 

Every time it was turned off it would it steam up again as if it had trapped the moisture. Eventually I recall sitting with the AC off, fans blasting and windows down for about 10-15 minutes. After that I stopped using the AC to clear the windows and just stuck with ventilation and normal fans. Didn’t suffer the same issue again. For that reason I don’t really like using the AC to clear condensation, just window open a crack and let the fans run.


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## Demented (Nov 3, 2014)

I'm not suggesting to use AC to clear the windows.

What I experienced and described, the AC was off but the blower motor had the option to operate all speeds whilst on Recirculate; when operated like this it would never clear the windscreen on a cold morning and when the screen was clear, the slightest change in weather condition and the windows would mist up, although the heater was hot and set to keep the screen clear.

Once I understood the meaning of the Recirculate setting and used it correctly, I've never experienced the windows misting up to such an extent since.


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## Marve (Jul 5, 2013)

I had this problem on my C3 recently. Always misted up when I got back into the car. Turned out the scuttle drains were blocked from leaves and debris so water was gathering there and consequently making the pollen filter soaking wet. So there I am every time trying to clear the windscreen with the A/C blowers on full and the air I am pulling in is going through a soaking wet pollen filter so adding to my problem rather than solving it. Drains cleared (the come out in the wheel arch) and filters replaced and the problem is solved.


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## djberney (Oct 2, 2016)

Just a little bump to say the Fog It is on sale at B & M for £3.99 (they sell the colgate at 99p as well if you're interested  )
Not connected to them in any way, just bumping up Mats thread count.


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## Alex L (Oct 25, 2005)

What about changing glass cleaner. I cant remember the scientific name, but some glass cleaners draw moisture in.

From memory if you leave a half bottle of Megs NXT glass cleaner open over night you'll have more of it in the morning. Thats why some glass cleaners leave you with misty glass in the mornings.


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## scooobydont (Feb 25, 2017)

Rain-X Anti Fog is £3 in Asda, picked some up tonight. They also have Rain-X for £3 also.


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