Defrosting windshield with water.

MetzgerMeister

Rubbing alcohol (IPA) and water mixed together is the homemade de-icer. You can add removing wax/sealants from paintwork to the list of things it's useful for. That means that if you wax your car, using this as a deicer may remove the wax.

The trick to using hot water is to pour it onto the roof of the car and let it fall down onto the windscreen. The heat is taken out of the water by the roof but it is still warm enough to melt the ice on the windscreen.

I fill a watering can with hot water from the tap, pour it in the middle of the roof and it de-ices all the windows in one go. There's also usually enough left to pour a bit on the wing mirrors too.

TheChizler

NiallBoo wrote: »

That's daft.

It isn't ethanol and would be toxic to drink.
If you can but mouthwash in a chemists there's no reason they couldn't sell that stuff.

I would have totally dismissed it if I didn't hear it from a few different pharmacists. Maybe they didn't know what it was and guessed.

Noccy_Mondy

Just keep your cars in the shed, like me....no ice, no problem.... peasants... :pac:

eeguy

Noccy_Mondy wrote: »

Just keep your cars in the shed, like me....no ice, no problem.... peasants... :pac:

Just get a sheet and throw it over the front and rear windscreen. Job done. It even keeps the bird sh*t off.

Dempsey

Deagol wrote: »

Surprised no one has mentioned that starting your car and leaving it idling on a cold morning is bad for the engine.

Reason; the fuel system dumps extra fuel in to run the engine rich in the cold. This essentially acts as a solvent and washes the oil away from the cylinder rings etc.

All manufacturers that I'm aware of recommend you do not leave your car idling unnecessarily.

Oh, it's also not good from environmental standpoint either

From a personal stand point, luke warm water works fine. After 25 winters doing it I've not cracked a windscreen yet. The mrs was using very hot water (think just boiled kettle) for several years before I spotted her doing it also without a problem! Though I'd not recommend that

All modern engines rev slightly higher when the engine is cold until its warmed up and can adjust fuel mix to suit the conditions its opetating in

BunkMoreland

Methylated spirits from the hardware should do the same job as rubbing alcohol. I wonder what it would do, if anything, to the paint.

I cracked my screen with too hot water before. There was an imperfection in the glass and a family member boiled the kettle too much.

Bearly warm, room temperature is enough and pour on the roof first to gradually up the temp of the glass.

Popoutman

If the day is going to remain cold, do everyone around you a favour and do not use water to remove the ice.

During the cold snaps 2009/2010 some of my idiot neighbours used buckets (literally) of warm water to attempt to deice their car windows, resulting in large buildups of ice on the ground where the cars were parked. Given there were no individual driveways, people were slipping and getting hurt as a direct result of people's thoughtlessness. More than a few broken windscreens as well, by using water that was hot instead of lukewarm or cool.

A properly clean windscreen ices up less. I keep mine very clean and the use of RainX goes a long way to making it ice much less than the other cars in the same area. Makes a big difference.

When it is iced up, I can start the car if I want and properly lock it with the spare key, removing the possibility of some miscreant being given an easy opportunity. Generally though I don't need to do that anyway. I just use a decent quality ice scraper and I can get all windows cleared in less time than it takes the neighbour to fill their saucepans. No refrozen water on the ground for someone else to slip on, and I'm out the gate in less time as well with clearer windows.

If you have a relatively modern diesel car, especially those higher in the range, you may have an auxiliary heater onboard. My Q7 has one same as all Q7s, and I've been able to enable the timer on that so that I can have a warmed engine and cabin, with de-iced windows, automatically done before I leave the house at all. As the engine is up to temp, there's less wear on the engine at start, lower emissions, and more comfort as well. It actually works out more economical too to pre-heat with the auxiliary heater than to start the engine and warm up that way.

9935452

the_pen_turner wrote: »

could you get an infrared heater and put it on a wall in front of the car. a few min should heat the windscrean. you could put it on a timer or remote

A friend had an old landrover which eithre didnt have a heater or it wasnt working . He drove it as a daily driver. In frosty weather he had a blo torch for defrosting the windscreen

johndaman66 wrote: »

Cold water out of the tap has never done a decent job for me. Luke warm as in 40 degrees Celsius maximum has always worked well and never damaged a windscreen or any other glass in many years of using it. Trouble here being peoples definition of what is luke warm will vary so widely. For some it will be just shy of boiling which is too hot and could potentially break a windscreen.


Also I wouldn't lob it onto the windscreen in one large splash, rather pour it slowly from along the top down and you wont cause such a shock to the glass which is what breaks it.

I used to live 1.5 miles from work. 4 minute drive. I never factored in the few minutes for the kettle to boil into my travel time so that alone could make me late . I used to get my hot water from the electric shower .
Im wondering has anyone else done the same.

TheChizler wrote: »

I've asked for it in a few pharmacies and they all claimed they couldn't sell it because of alcohol licencing laws. Was very surprised.

Maplin sell it too . About 20 euros a litre
We use it at work and are the biggest users of it in ireland . Its delivered by the tanker load. One a day i think

christy02 wrote: »

Start car, air con on full, drive up road with head out of drivers window until it clears. Usually cos I'm already late for work lol. No problem.

The problem i find with doing that is the drivers window freezes too so wont open

monkeysnapper

My car has a anti theft device that let's me run it on a cold morning .

Its called a 10 year old French car . .......they prob wouldn't get far .

Stravos Murphy

Having diesels idling for period of time is bad for the engine long term, wash the cylinders.

blackbox

coylemj wrote: »

If the windscreen is covered with ice, the ice is at 0 C and it and the glass can't get any colder, the layer of ice will literally 'heat' the glass to keep it at zero if the air temperature goes lower.

NOPE. Both ice and glass can go as low as ambient temperature. You may be confusing this with the fact that pure water cannot go below zero deg C and ice cannot go ABOVE zero deg C.

I agree about lukewarm water though. I've been using it for more than 30 years with no problems. Might be different if we lived in Northern Canada.

Dempsey

Stravos Murphy wrote: »

Having diesels idling for period of time is bad for the engine long term, wash the cylinders.

ECU will manage idling so no damage is done.

Alot of ****e spouted in this thread about damage to engines idling!! Where do ye get this nonsense?

Stravos Murphy

If the ecu will give a high idle. Anyone with any motoring knowledge partically Diesel engines are aware of liner washing. If you think it's fairytales think away.

Dempsey

Stravos Murphy wrote: »

If the ecu will give a high idle. Anyone with any motoring knowledge partically Diesel engines are aware of liner washing. If you think it's fairytales think away.

You are grossly overstating the risk to an engine by idling and people defrosting windshields will not be idling engines that long anyways

Stravos Murphy

How long is long? Will your fancy ecu work that one out?

Dempsey

Stravos Murphy wrote: »

How long is long? Will your fancy ecu work that one out?

ECU's have fault management so yes it will work that out :rolleyes:

Stravos Murphy

That's brilliant, thanks.

mycro2013

Pour the water from the boiled kettle on to the roof of thé car and allow it to run down thé windscreen and side windows.you 'll never crack your windscreen again.

Goose81

Some amount of **** posted in here about idling engines, diesel or petrol. unless it's a highly tuned car, supercar or a superbike I wouldn't worry about warming up /idling engines or if doing so will do any harm to it. These are bog standard road cars ffs, if idling will supposedly do them harm god forbid you actually drove it.

On the windscreen, I just throw on a half boiled kettle. Never damaged the window in 15 years, if it did insurance will pay anyway.

cnocbui

These suggestions for pouring hot water on the roof to cool it are amusing.

honda boi

Goose81 wrote: »

Some amount of **** posted in here about idling engines, diesel or petrol. unless it's a highly tuned car, supercar or a superbike I wouldn't worry about warming up /idling engines or if doing so will do any harm to it. These are bog standard road cars ffs, if idling will supposedly do them harm god forbid you actually drove it.

On the windscreen, I just throw on a half boiled kettle. Never damaged the window in 15 years, if it did insurance will pay anyway.

Me with my limited mechanical knowledge thought warming the engine up for abit would be good for the engine.

Del2005

honda boi wrote: »

Me with my limited mechanical knowledge thought warming the engine up for abit would be good for the engine.

The vast majority of drivers, myself included sometimes, have no idea how to warm up an engine. It should be done when driving and using low revs, but not so low as to labour the engine, and it takes a hell of a lot longer for the engine to be up to correct temperature than people think especially if you have to clear ice or frost off it. I often hear people start their cars and then slip the clutch and rev way to high when it's possible to move the car on tick over, they aren't doing anything good to their car but usually they are the same ones who don't service anyway.

Leaving a car idle is OK but wasteful as it'll take longer to get to the correct temperature, garages do it all the time if there's a suspected issue with the heating or thermostat.

grogi

veetwin wrote: »

Just be aware that during Step 3 thefts of very fine cars are common place on frosty mornings. No way would I leave my car running while unattended.

I can take the key from the car and lock it. It will keep running...

grogi

MetzgerMeister wrote: »

Rubbing alcohol (IPA) and water mixed together is the homemade de-icer. You can add removing wax/sealants from paintwork to the list of things it's useful for. That means that if you wax your car, using this as a deicer may remove the wax.

The trick to using hot water is to pour it onto the roof of the car and let it fall down onto the windscreen. The heat is taken out of the water by the roof but it is still warm enough to melt the ice on the windscreen.

Why not use warm water and apply to the windscreen directly?

CiniO

I always use the ice scraper to remove ice from windows, and soft brush to remove snow from windows and car body.
Only then start the car and drive off.
If below -10 deg, I would let it warm up for about 30 seconds before driving off.
If below -20 deg, I would let it run for about 2 minutes before driving off.

So far this always worked for me.

I never tried a trick with pouring lukewarm water, but I think it's silly.

grogi

CiniO wrote: »

I always use the ice scraper to remove ice from windows, and soft brush to remove snow from windows and car body.
Only then start the car and drive off.
If below -10 deg, I would let it warp up for about 30 seconds before driving off.
If below -20 deg, I would let it run for about 2 minutes before driving off.

So far this always worked for me.

I never tried a trick with pouring lukewarm water, but I think it's silly.

Water is dangerous - if it is feezing outside, it will turn into ice notime... Ice on the driveway - lethal...

MetzgerMeister

grogi wrote: »

Why not use warm water and apply to the windscreen directly?

Have you read the thread so far

grogi

MetzgerMeister wrote: »

Have you read the thread so far

I am simply asking what a physics principle makes it different to let the water cool down on the roof and to apply equally cold water directly. Apparently the first one is safe, the second not...

Because to me it sounds like superstitious Mambo Jumbo.

Honestly in over 30 years of everyone I know with a car using warm water to defrost a windscreen (including 10 years of having my own car and doing it myself every frosty morning) I've never once heard of it doing any damage. It might not be a myth but its so rare I think you have much more chance of breaking the windscreen by crashing than with warm water.

Del2005

grogi wrote: »

Water is dangerous - if it is feezing outside, it will turn into ice notime... Ice on the driveway - lethal...

That's only if you pour litres of water onto the windows, I can clear mine and the water doesn't reach the bottom of the door.