The last few cold nights, I cranked the red/blue lever on my Honda to full hot
and pushed the picture of a front windshield defroster to clear the windshield. Moved the blower motor lever to High.
The windshield cracked. The crack got longer the second night when I set the controls again the same way.
3rd night I pushed the button that says "heater", and the windshield took longer to clear, but no crack increase.

The Accord has one awesome heater, but does this, or has this, happened to anyone else? I got the car used, and the windshield was aftermarket.

Is there a serious way to stop this from happening with the next windshield?
I don't want to replace it and have to do it twice......or more.
Any thoughts on this? Thanks. -Bob

 

It is very possible... Its like taking a glass from the freezer, and putting hot liquid in it...

 

i dont see this happeneing..do to it take a while to build up heat for it comes from the motor colent,so unless you starterd your car and let it idle for 20mins then i think its B.S. cause iw ork at mcdonalds and 3days ago i had ice on my windshield so i went back inside and got a cup of hot water pured it cleared the ice right up not one problem

 

im sorry to say i dont believe that can happen...im from ny and have had a 1/4 inch of ice with 6 inchs of snow on top of that...nothing like that has ever happend to anyone ive ever met...what most likely happend is a rock or pebble got kicked up on to your windshield...if what u were saying could happen everyone up north would have to change there windshield on a regular basis...

 

Not saying it is probable, or likely or anything like that... Just saying, in theory, it is possible...

 

it is possible if he held a pencil torch to it other wize..no way...between the shitty pothole roads,construction,dump trucks and dirt roads there are plenty of other ways to get a crack

 

I lived briefly in NY city. You folks have some deadly cold winters!

The reason I think it was the super hot defroster on a super cold windshield, is that it cracked originally under those conditions; and the crack EXTENDED under those conditions when I did it again.

Since then, I have set the push buttons to "heat" instead of "defrost front windshield" ........and it has not cracked/extended the crack anymore. It takes longer to clear the windshield, but I'm willing to accept the tradeoff compared to getting more cracking. -Bob

 

usually a cracked windshield will continue to extend the crack over time so dont be suprized if it gets bigger

 

Well, thermal expansion will cause cracks in things, but I've never heard of a windshield doing it on its own. My theory, without knowing too much, is there was already a hairline crack that became worse after being subjected to the warmer temperatures (thus expanding the glass). Now remember, though, that it takes a great deal of energy to heat a windshield...it's a big dual-layered piece of glass, otherwise known as an insulator. One way to check to see if there's been a significant temp difference is to put your hand on the windshield. My guess is it'll still be pretty cold, especially if you've been driving and not just sitting there (though I wouldn't recommend playing while driving...that would just be plain irresponsible )