I received a call to do a cleaning on a KitchenAid double wall oven where the inside glass panel on the oven door exploded for no apparent reason. Upon arrival, a majority of the glass was cleaned up but there was still a lot of small pieces of glass imbedded into every crevice as well as the interior of the oven was coated with a fine layer of glass dust and particulates. The owners stated they had some remodeling work done recently and the contractor turned the ovens self clean mode on when the glass exploded. My first reaction was the contractor did something to cause this but the owner stood firm as this was not the case.
While I hadn’t personally seen the glass on an oven door shattered before, I have heard of it happening. In my research to see what would cause this it came to light that this is a more common issue than I realized. But how does this happen – how can the glass explode for no apparent reason? Isn’t the glass tempered and supposed to be stronger than normal glass?
Is it common for oven door glass to explode for no reason?
I did some research online and could not find an exact number of complaints filed each year. There didn’t seem to be one manufacturer with more complaints over another or if it was more common for the interior glass to explode over the exterior glass or vice-verse. While there appears to be no centrally documented place where the majority of complaints are made, I did notice there are hundreds of complaints littering the web from people with all the same testimonial of hearing an explosion in their kitchen and finding a million pieces of glass all over their kitchen floor. A few complaints that the glass exploded during the self clean mode while quite a few complained the glass exploded when they hadn’t even used the oven in a few days.
In a consumer news brief by KOMO Channel 4 News in Seattle they state “Repair experts point out that the number of glass shattering cases is relatively small compared to the millions of ovens on the market. But, given the pages of federal incident reports, consumer who’ve dealt with the problem wonder why there have been no safety alerts.” GlassPaint H2O Pre-Mixed
What is tempered glass?
The glass on your oven door is tempered. Tempered glass by definition according to the National Glass Association (NGA) “A strong break-resistant type of safety glass that, if broken, shatters into small granular pieces. Glass heat-treated to withstand greater than normal forces on its surface” Uhh..sure, that explains a lot!? How about – Tempered glass is manufactured using high heat and a rapid cool down making it four to five times stronger than normal glass. When tempered glass breaks it is designed to “explode” into small oval-shaped pebbles or pieces instead of shards. Tempered glass can withstand high heat and heavy loads but can also be very brittle especially around the edges and when subjected to blunt force from something with a point.
What causes tempered glass to break?
During the process of tempering the glass is heated upwards of 720 degrees and rapidly cooled using cool air to change its molecular structure. It is not uncommon for the glass to develop small unseen stress fractures during this process. These stress fractures may break during the tempering process or may never break, there’s just no guarantee what will happen or when.
What are the manufacturer’s doing about this?
The typical universal statement will be “We take consumer safety serious”; sure you are but what are you doing about it? Other than “looking into the matter” and in a few cases replacing the glass for free, they are basically doing nothing about it. Why? Because there isn’t anything they can do about it; they have no control over the glass making process nor can they guarantee the glass won’t ever break.