Has your oven door shattered?

Glass can vary considerably in composition and toughened glass can break because of small imperfections that create points of weakness that can lead to ‘explosions’. Duncan Lucas has discussed this in detail in the context of mobile phone screen breakage.

The key feature of borosilicate glass is that is resistant to breakage due to rapid changes in temperature, unlike most other glasses that we have round the home. Pyrex used to be synonymous with borosilicate glass but the name is used for cheaper soda glass in the US. Soda glass is not heat resistant.

When cleaning oven doors it is important to avoid abrasive cleaners and not to use oven cleaners that contain sodium hydroxide. Sodium hydroxide is alkaline and can destroy the smooth surface of glass, making it more likely to break and even making it opaque. For the same reason, drinking glasses are best kept out of dishwashers. Oven doors are best cleaned after use and it’s best to keep food towards the back and covered if possible.

That worked for me too. I did use detergent but no abrasive cleaners.. I had an inner glass door that lifted out of the main oven and it was easy to remove and clean regularly.

If you read my post of the 13th May Border Reiver you will find ,its a beyond doubt/proven fact (at least in the USA ) that continuous use of the oven cleaning facility will eventually weaken the glass doors of the oven .This is backed up by the US Federal Authorities who have the US figures . The problem is it isn’t published by the makers as a flaw but as an additional BENEFIT ! Border Reiver ? any relation to the Duke of Buccleugh , Northumberland used to be owned by Scotland and previously the Vikings QE 1 thought a lot of them as fighters. Plenty of folk songs about them and the clans in that area.

The company your link goes to Kenneth is a commercial spares for domestic appliances company , while it gives good advice -as far as it goes – thats the problem its left an “elephant in the room ” as it is not willing to “upset ” the people its business depends on -ie- the manufacturers – read my post of 15-5-2017 . I have downloaded a whole webpage from from the FTC website on a massive investigation into exploding oven doors , taking in the whole of the USA and questioning all the families involved in those incidents , the model+make of oven etc and the conclusion reached was that a large number were caused by the manufacturer,s OWN advertising of an “additional Luxury feature ” -ie- the self -cleaning mode which , by its actions increased the internal temperature well above that of the manufacture of tempered glass thereby causing long term damage (weakening ) of the glass. Of course NO manufacturer is going to print that especially in this country where its a policy of -hide the truth from the public right across the board . Why-oh why ? do I have to go to the Home of Capitalism to get the truth , it makes me admire the American openness in this regard as opposed to UK -need to know -wartime basis which is getting worse by the minute . On every level its -keep it secret . If the US is going to takeover the UK I hope at least this type of thing is incorporated into UK (US) Legislation.

Why oh why must every response be something to do with the USA which, is far from perfect? 😉

And if you go out there on the big bad internet you’ll almost always find an opposing view or study as there’s usually interests involved be it consumer or business or governments or academic or whatever. Doesn’t mean to say any one is completely definitive as the one you mention likely isn’t, that I’m not bothering to read as it will not apply to EU product.

However Duncan, can you accept that I have over 25 years experience in dealing with this stuff right here in the UK and I know a ton more about it than most people ever will?

If you accept that then please accept that the information there is not to drive sales, it is intended to inform people and demonstrate the reasons why oven glass fails.

Despite the not-so-veiled inference, if you read many articles I’ve written you will find many of them to be deeply disparaging of the industry, some even call into question the general practices of many brands who can be seen to often trade on a fine line between what they can get away with and what’s legal.

So I’m sorry Duncan but I have to defend my corner here and say that your take is wrong, it is not as you allude to at all.

The vast bulk of info on there is written to help people. If you don’t want to see it that way, that is of course your prerogative but it’s comments like these that make myself and others think, “why should we bother, you try to help people an all you do is get a kicking for it, what’s the point?”.

It’s a sure fire way to ensure people get minimal or no help at all.

K.

According to what I have found, self cleaning ovens work at temperatures of between 500 to 900F whereas glass is heated well past this to around 1150F in the toughening process. There is no secrecy that I can find.

Quite right Patrick; it is a question of putting matters into proportion. Those proportions rarely feature because that might detract from the impact.

Hi Lauren, if you’d asked me… 😉

It’s a pretty common thing to happen but there are any number of reasons for it to happen as pointed out in that article, most of them nothing at all to do with design whatsoever, it’s just the nature of the beast.

Some are more common than others for sure but then, without comparative sales figures to get an idea of how many are in service using particular panel it’s impossible to even guess at the actual failure rate. Which is where most research in the area falls over as, you are guessing at numbers.

To illustrate, one common Beko, Bosch or whatever glass panel may well be fitted to ten or two hundred models. You need to find that out first.

How long have they been on sale, how many are still in service, how old were then when they failed, how much use have they had, general condition of the appliance… the list goes on of things that would need to be well documented and demonstrated in order to form any substantive opinion.

You may be able to isolate a particular part, model or even perhaps brand but in my experience, probably not as they all suffer from it to one degree or another as this does happen through general wear and tear.

And, it’s been happening way back to the eighties so, it’s nothing new.

Frequency wise, I’d not think there much difference across that 30+ year period.

Other than the odd blip with the like of the Whirlpool ones of old that Watchdog went into but, that was dodgy brackets that allowed the panel to move, it scored, it blew. Lessons were learned and there’s never been a similar occurrence across the industry that I know of.

I essence so long as people want glass doors that they can see into the oven through, this will happen and I would think it wholly unavoidable. If that style is required by users then I’m afraid it’s just something everyone will have to live with.

My cooker, it’s got solid steel doors.

K.

“Frequency wise, I’d not think there much difference across that 30+ year period.”

So in your experience how often does it happen Ken ?

To belabour the point if every member who joined Which? was asked to track and complete some survey we would have hard figures. Which? already has the Connect resource which has been running for decades albeit not branded Connect.

I know I have completed surveys on ovens etc and it asks if you have had repairs or problems. Has nobody bothered to extract the broken glass responses? Which? you do have the data you are just not using it.

As an example of joined up synergy this ain’t it.

It’s a frequent failure essentially.

Probably easily several a day in one form or another but from my own experience in the field seeing them, that’s not exactly a shock with grease and whatnot covering the door glasses. So much so I wonder why people bother with it as that’s what will happen unless you religiously clean them then when they are cleaned it’s often with a Brillo pad or something to attack the built up crust on them. They get scored, they blow.

Then there’s the glass seals failing or they just get loose and move. They score, they blow.

Or a plethora of other reasons why it happens.

But the crux of it is that it’s an insert piece of material and barring some sort of shock, be that mechanical or thermal, they will just go on forever. Some do, probably the vast majority by some margin will never fail as it’s far from uncommon to see 20+ year old product with intact glass on it even when the same model/s have been common for glass failure which would suggest strongly that it’s a use thing rather than a design thing.

Or perhaps just luck in some cases, I’d accept that.

I have seen manufacturers investigate failures and having them analysed a couple of times or so and none proved a problem with the glass as such.

As I said, the old Whirlpool on, we’ll known problem that wasn’t before that all happened and, it hasn’t happened since as everyone knows this now.

But the key bit of info is that, if a glass gets scored, even slightly then it will go, it’s just a matter of time till it does. Could be a minute, hour, month, year… who knows but, it will go.

You can see the same on some glazing stuff as well, they’ve got the same issue I am informed.

K.

Ken – when you say several a day you are talking presumably as a centre for questions and parts. Just to clarify that you are not speaking as an electrician going out on daily jobs replacing broken glass.

So if we multiply your daily experience with the few other on-line contact points we should have a sense of the numbers involved.

As I have said I AFAIR over the four or five years been asked twice on major kitchen appliances and reliability and brand. Which specifically ask questions on problems. I assume that people who have had an exploding door in the previous three years or however long the period is will mention it. On that basis Which? should be able to provide the number of surveys completed and the number of reported door incidents and the Brand/model.

This figure could be scaled to provide an idea of incidence.

I wonder if Which? have written to the various manufacturers and simply asked how many replacement glass doors have been requested. Non-answers in themselves are interesting, Who knows some might even reply and talk in technical terms that may interest the geeky readers here.

Checking back it was 2015 September 4th I completed a survey asking amongst other items about my ovens. The Ikea oven was fitted in 2008 and was included in the supplementary questions on faults and had I repaired it.

Given the numbers involved in the surveys I would think Which? has data on ovens from at least 4000 people which is less than two years old.

“Polls have shown that, when asked whom they trust, Germans answer: family, friends and the Stiftung Warentest. …. That it has remained focused on testing may say something about Germany’s business culture too, reflecting how, in the German-speaking world, cold hard facts tend to trump spin.” FT

Duncan, it does happen. No doubt about it. No denial at all.

But it is just the nature of the beast as explained rather in depth. Unless someone comes up with a better way to form glass or, you can remove the heat/cool by altering the physics, you can stop people from letting the glass get grubby with detritus and grease and on and on, you’ll never solve the fundamental problem as, without some change or many, this is inevitable and keep on happening.

If people want glass doors then, I’m sorry but buyers will just have to accept it can happen.

So yeah, the FTC will find this happens, anyone with a pen, clipboard and a bit of time could work that out.

If people wish to avoid it, go for a machine with solid doors. It’s a very simple and effective solution and we did, after all, manage without glass doors on ovens for several centuries just fine.

Pyro ovens are different as they invariably have at least three panes of glass, driven air cooled, locks and a load of other key differences to a standard oven door to withstand temps of 400-450˚C+ on a pyro cycle. This also means that they are subject to massive temperature differentials and, if not cared for (i.e. get too dirty) they probably may well fail more.

Most you see i the field are streaked internally due to that and cleaning gunk from improper cleaning… like mostly all of them.

Try telling a customer that’s bought a £500-1000+ oven they’re not cleaning it properly, it’s not a pleasant response you get. And, as the pyro doors are built to withstand these high temps they’re harder to take apart to clean, another compromise.

In the end, buyers want glass doors and pyro functions and that’s fine. If they research both they’ll find there’s compromises that have to be made to get each or both.

If they don’t research, that’s on them.

If they can’t accept the compromises then what do you reasonably expect anyone to do about that?

It’s like me impulse buying a PC only to find it’s more virus prone than Mac then whining about it… it’ll fall on deaf ears.

Providing that information is what Which? is all about in my opinion.

K.

Quite right Ken. Which? should provide the data and interpret it in a meaningful way for subscribers.

I have always been faintly irritated by the detail in some surveys that is never used, plus lightweight questions. When Connect was started we were promised access to the raw data as a reward for taking part I suppose. This offer was never put into place other than a dead link.

I am sure I could easily speed read 4000 survey returns in a day to find the few that have glass door problems. Using a scanning system would of course be far quicker but I am happy to help out.

The trade off in high temp cleaning options and increased chances of a broken glass event surely is explicit advice Which? should give. But then it does need quantifying.

As someone guilty of cleaning with wire wool 0000 grade, I am curious as to whether it is a dangerous practice.

en.wikipedia.org/wiki/Steel_wool

Anything that can score the glass weakens it in essence, it puts fractures in the outer “skin” that holds it all together. Ultimately over time that will weaken it and ka-blooey, it blows.

It will often seem completely random, the appliance can be switched off totally, unused and it is said that even just sunlight hitting it cause it to expand/contract at an uneven rate and those micro fractures just rupture and, game over for the glass.

So my general advice is, don’t go near them with anything that’s abrasive at all or you invite the possibility of it blowing or at least making it more likely.

This is why most can be removed for cleaning, hot water, mild detergent, non abrasive stuff and it’s absolutely fine to clean that way. Keeping them clean is also important or, again it can stress the glass and it’ll go.

K.

Its usually caused by minute imperfection in the glass Mick which arent easily removed in its manufacture, unless, of coarse , its for the defense industry.

Ann-Stress particles in the glass could build up if the door is constantly slammed shut over a long period otherwise large changes in the temperature due to an oven cleaning facility which heats the glass up to danger level, again over time . If it was just a case of a flawed glass it would have gone before 5 years.

I would be very happy to have a washing machine with a metal door. The only benefit of having a glass door in my current machine is that I have watched laundry detergent capsules and bits of tablets becoming trapped in the door seal and still there during the rinsing process. 🙁

It would be nice to have the option of buying ovens and washing machines with metal doors. I expect they would appeal to anyone who had suffered an explosion.

Our parents turned out fantastic dinners with metal oven doors. They knew when to open the door for a quick look at the roast or the cake. I have no objection to a window in the door but I think it introduces another point of weakness and potential safety hazard.

Jean,
The danger is getting these problems out of proportion. Considering the number of ovens with toughened glass doors that are in use, breakages are extremely rare.

Although this link is 4 years old, an oven valeting company reported on their experience. You might find this interesting to read as it gives information on why toughened glass might break, as well as their instances of breakages.
An extract: “This leaves just 57 instances out of 295,334 completed jobs where oven door glass shattered for no apparent reason. This figure is just under 9 cases a year.
As a percentage, the 57 ‘mystery’ cases represent just 0.02% … again, put in a slightly different way, a solitary ONE instance per 5,000 jobs undertaken.”

https://www.ovenu.co.uk/shattered-oven-door-glass-survey/