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On STWv1 forum, there was a thread about defrosting car windscreens with ho****er. On camp saying "it will crack" another saying "it will probably only crack if there's a chip in your screen".
I just cracked my screen this morning, and have no recollection of a chip/crack at either end 🙁
I've defrosted this way for 20 plus years & not had a problem but I do only use 20C water.
Use cold water numpty, it still defrosts it 😀
yup, cold water here too for last 15 years with no probs
turn your engine on, turn the heater on and use a window scraper with a bit of effort behind it.
you don't need water or de-icer or anything. usually just makes it harder, IME.
Use a bank/credit card to take the ice off - better than any scraper.
Heated windscreen on my Mondeo. What is this scraping of which you speak?
Use cold water numpty, it still defrosts it
Gah.I guess it was hotter than I thought it was, and quite cold out.
Like I say - never had it happen before. Glad it was my gash alfa, not the wifes nice car.
clear your shed out & put the car inside 😆
HTH
Insurance will cover it, won't it?
>Insurance will cover it, won't it?
Yes, even idiocy in this case.
i have always used warm water on my cars , never had any issues at all.
even my car with lightweight thiner glass (i kid you not)hasn't cracked........ yet
why not just start the car up, put the blower on full blast and go back inside for a cuppa tea ?
While someone steals your car? 😉
Yup,also a warm water user for over 25 years(when we used to have proppa winters)& no ****ed screens here either....
Wife's car got a heated front screen & it aint as quick as the water method 8)
use cold water,
hot water actually freezes faster than cold water,
i dont understand the physics behind it,
but if you dont believe me just google it
warm water & wipers on fast is the way to go....
Used a CD case impromptu yesterday to de-ice. Worked a treat and no icy fingers of using credit card technique.
"hot water actually freezes faster than cold water"
its on the internet so it must be true!
think about it logicaly for a few seconds.............................
high tempreature water in a bucket (90deg C), low tempreature water (20deg C) in an idetical bucket (no treadmills or aeropanes involved)
presume ground is perfectly coducting and has a tempreature of -10deg C, and the air tempeature is -10deg C
The rate of evaporation (and so cooling by the enthalpy of vapourisation) is (for the sake of argument assumed to be, we wont go into 5 film theory, an convection currents) proportional to tempreature. Ditto the rate of heat loss by conduction.
So initialy the hot bucket loses heat (and thus lowers in tempreature) at a greater rate than the low tempreature bucket.
But as it cools this rate lowers.
so when the high tempreature bucket is at 20deg C, its rate of heat loss will be the same as the low tempreature bucket was originaly, however, the low temp bucket has now cooled to 5 deg, etc etc etc
Yes i have heard of the Mpemba pheomenon, but that only aplies in certain coditions, in reality you'd have to devise your experiment to take advantage of it.
oh gawd here we go again,
you put the hot water into a airplane shaped ice cube tray,
then straight into a freezer which is on a conveyor belt
thisisnotaspoon that's what i thought the cold water has a head start in freezing
no!!!!
check out my last paragraph, its a phenomenon that exists, i dont doubt that, but thats like saying everyone drives bugatti's, based on the evience that 1 person does.
start engine, back in side, cup o tea, back out window clear .mainly with frost but if its heavy snow it helps as well because you just brush the snow of with big brush
the 2 buckets is the precise experiment where hot water will freeze before the cold, given that they are in the same environment.
dont poo-poo the idea, i remember seeing it on a children's program, it might have been "how 2"
and they dont lie 🙂
stand on the roof and piss all over the windscreen, cleared in seconds...
Used water on car screens for years clears it instantly and never had one crack. No doubt it can happen with hot enough water and a really cold day.
wouldnt just be 2 buckets, the buckets would need to be the right shape/size and filled to the correct level as well,
and it presumes no forced convection, i.e. your not stirring it, so the situation where its runnig down your windscreen in a very thin film, is probably about as likely to exibit the Mpemba phenomenon as i am to win the lottery (nearly impossibe seeing as i dont play)
Colande sounds to me as if he knows what he's talking about.
You on the other hand Spoony, what you're saying just sounds like nonsense to me.
.
Plus, you don't appear to have watched the children's programme which he's talking about.
grizzlygus - Member
Colande sounds to me as if he knows what he's talking about.You on the other hand Spoony, what you're saying just sounds like nonsense to me.
Plus, you don't appear to have watched the children's programme which he's talking about.
😀 haha grizzlygus, seeing that he hasn't seen the children's program in question i pronounce myself the winner,
edit; http://www.discoverychannel.co.uk/web/mythbusters/experiment/ice/
no ive not seen the TV program............................
but i did research it for part of my degree :p
Same here, I use lukewarm water and it clears all the windows with one jug full. Put wipers on and it's dry so it won't freeze again.
Very hot water just seems a bit extreme!
i did research it for part of my degree
So how come you don't know about the experiment then ?
Did I and other taxpayers pay for your degree level education ffs ?
Pour it on the front of the roof and let it run down the screen, works for me. But there again I onlt have to do it once in a blue moon as I ride to work all week.
Water that has been boiled (but then allowed to cool to ambient temperature) will freeze quicker than cold (ambient temperature) water.
It's about the air content within the water.
Start the car ,lock the car then go in for tea.
I tried the water method but it ended up in the locks and then they would freeze up, Don't suppose that matters as much with the remote locking now come to think of it
I'm a W/Screen tech. and can't believe u tworts use hot water to clear ure screens !!!
You all deserve to have your W/S excess's TREBBLED !!!! 
scraping the windscreen takes approx 30 seconds and, unless you use a brick, doesn't break it.
Another happy user of ford's heated windscreen here 😀
Also loving my Ford Quick Clear windscreen here. I juts have to start it up, scrape the 4 side windows and the front is done!
Yep also loving the QuickClear.
Though I can go one better: I just get in and say "Defrosting on!" in my best Captain Picard voice.
Front and back windows heat up, blowers come on for the side windows, wing mirrors heat up and my washer water is also heated.
Meantime I sitback and quietly chortle at the guy turning blue who has just broken his credit card on his window.
Toys are great!
loving the heated windscreen on my mondy too, but why dont Ford licence it to other manufacturers?
I just get in and say "Defrosting on!" in my best Captain Picard voice.
Must be a bit of bugger if you get laryngitis in winter then. As not only will you have a sore throat, but you can't drive your car anywhere - poor you 😯
Scraping seems to work for me. You've got to clear all the windows anyway not just the windscreen. Plus, even if you clear the outside of the windows of ice, the inside fogs up in really cold weather until there's some warm air blasting out, air con or not. My wife starts the car, puts the screen heaters on at full and then locks the car with the other key and goes back inside for a cup of tea.
Just clear a small slot in the screen, jump in the car and go.
grizlygus, thats a bit harsh, and i did mention the effect, its called the Mpemba effect/phenomenon after they guy who re-discovered it, but the effects been known for hundreds of years.
Several hypothesis' for why it happens;
convection (the one i looked at)
gas content (proven not to be significant if at all)
supercooling (unlikely, this only hapens in perfectly polished containers with absolutely no contaminents)
solutes (would have an effect, but not at the levels foud i tap water, maybe if you used batter?)
in basic terms i was trying to show that the inertia of a convection current could sustain a warmer layer of liqid on the surface of a container, thus increacing th evaporation rate.
The answer was yes, it can be made to cool faster.
Other things that affect it are the way the ice forms, the cold beaker with no/little covection would form ice on the surface, thus blocking further heat loss, and slowing down its freezing. The warm beaker maintains warm water at the surface (increacing evaporation) and freezes from the bottom.
Gas content has been rueled out, you can repeat the experiment with two beakers of boiled water one at 90deg and one at 10deg, the same thig hapens.
However, i highly doubt the thin film of water flowing down your windscreen is moving slowly enough, and lasts long enough for the effect to occour.
I always imagined that it would be due to loss of a larger proportion of the hot water by evaporation, leaving less to freeze
oh, and my 15 year-old kit car has a heated windscreen (and sometimes my wife dresses up a lieutenant Uhuru and spanks me with a hairbrush)