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Best way to prevent ice build up on windscreen  
Best way to prevent ice build up on windscreen - TB2
Now that the cold weather is starting to take a grip around the country, our attention is drawn to carrying scrapers, windscreen de-frost, etc.

Is there any easy way to prevent the build up of frost and ice on the inside of the windscreen? I was wondering whether placing card or old carpet on the outside of the windscreen would help to keep one side of the windscreen slightly warmer and thus warm enough to ensure that any condensation etc remains as such on the inside rather than forming frost/ice. Would the use of a de-humidifier such as you can buy from camping shops for the use in caravans/boats be of any use?

It's quite frustrating to spend an extra 5 minutes or so scraping the inside of the windscreen each time I want to use my car during a particularly cold spell.

Tags: owning safety winter tyres warranties

Best way to prevent ice build up on windscreen - Dynamic Dave
It sounds like you have another underlying problem if the inside of your windscreen ices up. In the 24 yrs of motoring I've never had a car ice up on the inside of the glass.

What car have you got, and why is it getting so damp inside that it is able to ice up when cold?
Best way to prevent ice build up on windscreen - TB2
1989 Long Wheelbase Land Rover. Use it for personal use only, no business use. Only carries family and on occasions the pet Labrador.
Best way to prevent ice build up on windscreen - moonshine

Dehumidifiers tend not to work when its really cold as they ice up. Sounds like there is excessive damp/water getting in somehow. While carpet would stop ice forming on the outside as it forms a barrier, I dont think it would keep the screen warm enough to stop any internal condensation from forming and freezing. Cars lose heat very, very quickly.

Best way to prevent ice build up on windscreen - Pugugly
excessive damp/water getting in somehow

It's a Landie !!!
Best way to prevent ice build up on windscreen - Hamsafar
Don't use a de-icer spray on the outside, as this will cause frosting on the inside, due to the change of phase and enthalpy. To change the frost to water on the outside requires energy to break the molecular bonds, this is obtained from the glass, and so the windscreen which is already cold will be reduced significantly more to well below freezing and so frost will rapidly form on the inside.

To demonstrate this, fill a beaker with crushed ice cubes and water and stir it with a thermometer which should show 0degC, and then add a load of salt, you will see the temperature plummet as low as -15degC as the ice is melted and the outside of the beaker will start to frost over.

Edited by Hamsafar on 07/11/2009 at 21:50

Best way to prevent ice build up on windscreen - piston power
If this is a diesel you could fit a webasto heater the type that heats up the engines coolant it runs from a timer unit and runs at approx 70 deg heat settings adjustable and length of time on.

It will make engine starting much easier from cold due to the coolant been at temp the heat is there in the heaters.

Comes standard on some vehicles plenty on the likes of e bay, webasto in my opinion is the better make to fit.
Best way to prevent ice build up on windscreen - Fullchat
Nuff said!
Best way to prevent ice build up on windscreen - Stuartli
The cleaner you keep the inside of the windscreen the quicker any condensation will clear - it's the buildup of a film of dirt, oil fumes etc that allows condensation to "stick" to the screen and, presumably in your case, freeze up.
Best way to prevent ice build up on windscreen - Rattle
My old car did this, the solution was to always put the heater on cold before leaving it parked for the night. This stopped the coolant from entering the matrix which I suspect had a very minor leak.

Best way to prevent ice build up on windscreen - mike hannon
'change of phase and enthalpy'

Please explain the above to someone with an average brain.
Best way to prevent ice build up on windscreen - perro
(1) Make sure the windscreen is thoroughly clean.
(2) Leave air intake in "air circulate" as apposed to fresh air coming in if you have such a facility on a landie.
(3 Maybe try a thin coating of washing up liquid on the screen.
(4) Try an insulated screen cover like I used to use in my motor home.
(5) Try leaving some cat litter in the cab - in some sort of box/tin.
(6) Try living in Tenerife!
Best way to prevent ice build up on windscreen - Stuartli
Make sure the windscreen is thoroughly clean.>>

Maybe try a thin coating of washing up liquid on the screen.>>


The second comment completely opposes the first, correct suggestion, which I also made earlier in the thread.


Best way to prevent ice build up on windscreen - The Driver
If possible put a mains powered fan heater in the Landie 30 minutes before you need to use it.
Best way to prevent ice build up on windscreen - ifithelps
Try parking it the other way around/facing a different direction - unless you leave it in a field.
Best way to prevent ice build up on windscreen - Alby Back
Or....turn engine and heater on....have a cup of tea.....drive off.
Best way to prevent ice build up on windscreen - Pugugly
Oh Humph - I had the audacity to suggest that here a few years ago and was charged, convicted and sentenced for

1. Being solely responsible for the death of a million cuddly polar bears

2. And recklessly putting temptation in the way of the marauding drug addicts waiting for the opportunity to steal my car....:-(
Best way to prevent ice build up on windscreen - nortones2
If the freezing is local to the windscreen, rather than all the glass surfaces, is the screen seal perished/damaged?
Best way to prevent ice build up on windscreen - Pugugly
Nortines - there are just so many ways dampness/condensation can creep into a Landie - it's a characteristic the Character Builder option pack.
Best way to prevent ice build up on windscreen - nortones2
Agreed: I've spent many an hour in examples of the Defender.
Best way to prevent ice build up on windscreen - ifithelps
It's the exact opposite of the old Beetle where air pressure prevented you slamming a door unless a window was down a crack.
Best way to prevent ice build up on windscreen - Harleyman
As an alternative to leaving the engine running, you could maybe fit an Eberspacher heater, known to us lorryists as a night heater. Get one with a timer and your cab'll not only be dry but nice and warm as well!


Most of them will be 24 volt I suppose as lorries generally are, but AFAIK they're fitted to some campervans as well so 12 volt must be an option.
Best way to prevent ice build up on windscreen - TB2
Thanks for all the replies. I'm tempted by the prospect of an 'overnight' heater, but it's a V8 model and not a diesel; is this a problem?

I can't say that i've noticed excessive condensation on any of the other windows/glass (17 in total!) if at all; certainly not any build up of ice, except for the windscreen.

I've looked at the windscreen seal and it does look weathered and cracked in places, but no more so than around any of the other windows.

Apart from the inconvenience of scraping away, I was more concerned about the amount of water that would drain down onto the top of the 'dash' (if you can call it that?) especially over the instrument binnacle, if you left it to thaw naturally. Over time, this cannot be a good practice. I'm no mechanic, but water and electrics........!
Best way to prevent ice build up on windscreen - piston power
I'm tempted by the prospect of an 'overnight' heater, but it's a V8 model and not a diesel; is this a problem?


You would have to fit a small fuel tank for the diesel heater 4-5ltrs is enough but the better type of heater is the one that runs coolant around the v8 keeping it hot and easy starting better fuel consumption & best of all no icy windows and a hot cab heater when it's minus 3.!!
Best way to prevent ice build up on windscreen - L'escargot
Start the engine, set the heater to maximum heat and maximum airflow to the windscreen, and then get out of the car. Then scrape the outside of the windows, and don't get back into the driver's seat until both the inside and outside of the windscreen is clear.
Best way to prevent ice build up on windscreen - dimdip
TB2, can I ask: do you use the ventilation fan much? I know some people view them as for use in extreme circumstances only. The water that tends to get carried in during wet weather on coats, brollies, boots etc can linger if ventilation isn't high (and landies don't have particularly great heaters iirc?).

I tend to leave the fan on at a low setting all the time except on the motorway. Anyway, just a thought...
Best way to prevent ice build up on windscreen - L'escargot
Thoroughly dry out the interior of the car for a day or two using a mains-powered domestic dehumidifier, and then follow my previous suggestion for starting each journey.
Best way to prevent ice build up on windscreen - M.M
Suffered the same problem a few years back when we ran both series 2a and series 3 models as a third vehicle to visit our horses each day. These LRs would stand all day and then be started up to do a 3ml trip. Most of the winter they had condensation on the screen which was then frozen of cold nights. The LR heater was useless and hardly gave any warmth in such a short journey.

It didn't take long to work out that a mains fan heater put on the front seats blowing at the screen for 5mins was the only way to make the vehicle useable in winter.
Best way to prevent ice build up on windscreen - Reentrant
Are those 150w fan-heaters that plug into the cigar lighter socket any good? (lots advertised on eBay).

I'm quite happy pouring warm water onto the windscreen but SWMBO doesn't like the sheet ice it leaves on the driveway when I've gone.
Best way to prevent ice build up on windscreen - piston power
SWMBO doesn't like the sheet ice it leaves on the driveway when I've gone. You just can't win! lol........
Best way to prevent ice build up on windscreen - injection doc
Best device is one of these

www.kenlowe.com/pre-heaters/cars/spec.html

I have used them for years & on a petrol vehicle they save a fortune on fuel on short journeys & save exhaust systems etc. I used a timer on mine & it used to come on 20 mins before I left the house. Leave the heater vent on screen & the heat from the matrix will drift up & soften the frost. As soon as you start up you have a hot heater.

I have also stuck a mains dehumidifier in an old landy for a couple of days before just to dry all the moisture out that build up in the fabric etc & that reduces condensation
Best way to prevent ice build up on windscreen - M.M
....fabric

You had a luxury model then!
Best way to prevent ice build up on windscreen - FotheringtonThomas
If you can keep the whole thing from freezing, that's your best bet. A 79p squeegee from Lidl will remove the condensation double quick. A bank-card type piece of plastic is excellent for removing thin ice from glass.

For those owning cars with air conditioning, use that to remove condensation. It's wonderful, but for some reason people only ever seem to think of aircon as "for hot weather" - it's much more useful in the cold.

Edited by FotheringtonThomas on 12/11/2009 at 17:46

Best way to prevent ice build up on windscreen - henry k
>>For those owning cars with air conditioning, use that to remove condensation.
>>
The A/C will not work in freezing temps!
Best way to prevent ice build up on windscreen - DieselBoy {P}
"It's the exact opposite of the old Beetle where air pressure prevented you slamming a door unless a window was down a crack. "

Maybe when they were new, but not when 39 years old!

My wife's 1970 Beetle freezes up quite nicely on the inside in the winter. She has no heating at all (heat exchangers kaput - due to be sorted along with an engine swap in the next two weeks which will sort out the 3L of oil used/leaked a week).

We (I) find a hot water bottle placed on the open glovebox lid / balanced on top the steering wheel half an hour before needing to drive away, works quite well.
Best way to prevent ice build up on windscreen - FotheringtonThomas
The A/C will not work in freezing temps!


Why not?
Best way to prevent ice build up on windscreen - The Driver
They usually cut out at about +3c to stop the system freezing. (Evaporator I think.)
Best way to prevent ice build up on windscreen - L'escargot
For those owning cars with air conditioning use that to remove condensation. It's wonderful but
for some reason people only ever seem to think of aircon as "for hot weather"
- it's much more useful in the cold.


With my car (and the previous one) using the aircon in winter results in some of the extracted moisture being left somewhere in the heater/aircon system. It dries out eventually, but it takes a few days. Consequently, in the meantime, the moisture comes back into the car and mists up the screen when it's cold. Using the aircon to clear it again just creates a vicious circle of more residual moisture, so I avoid using the aircon in winter. Fortunately I have an electrically heated windscreen.
Best way to prevent ice build up on windscreen - piston power
Ideally have a large garage stick it in there with central heating boiler and radiator leave windows open i will dry out and be warm.

However the gas bill will be through the roof the wife will moan and will probably leave you. heaven!! lol........
Best way to prevent ice build up on windscreen - dimdip
>>With my car (and the previous one) using the aircon in winter results in some of the extracted moisture being left somewhere in the heater/aircon system. It dries out eventually, but it takes a few days. Consequently, in the meantime, the moisture comes back into the car and mists up the screen when it's cold. >>

I don't know the geography of car A/C, but with buildings there's always a condensate drain to remove what drips off the evap coil. Presumably cars will similarly have a drain line, so perhaps this is a symptom of the drain being blocked by mould / dust?
Best way to prevent ice build up on windscreen - The Driver
Yes, should be a drain, and there is usually a puddle of clean water under the car when the aircon is working in humid conditions. Often seen in car parks.

Edited by Old Navy on 13/11/2009 at 11:47

Best way to prevent ice build up on windscreen - FotheringtonThomas
I don't know the geography of car A/C but with buildings there's always a condensate
drain to remove what drips off the evap coil. Presumably cars will similarly have a
drain line so perhaps this is a symptom of the drain being blocked by mould
/ dust?


Probably. You should run the aircon every so often anyway, Winter or Summer. Set it to hot in Winter or you will freeze off your gearknob!
Best way to prevent ice build up on windscreen - Dynamic Dave
Using the aircon to clear it again just creates a vicious circle of more residual moisture so I avoid using the aircon in winter.


I leave mine on all year round (climate control) - but even with the most basic of air con systems you can still use it in conjunction with the heater controls - i.e. a manual version of climate control.
Best way to prevent ice build up on windscreen - The Driver
My car has manual aircon which I never turn off, the air is cooled and dried before it goes through the heater matrix so the temperature output will always be controlled by the temperature knob, and the air entering the car will be dry.

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