Grill element blows after three years - advice please.

[bobnotthe builder]

I bought a Bosch built in oven in 2007. Three years ago it "blew" - I'd noticed that prior to this, one end of the grill element was gradually twisting downwards from the ceiling of the oven.

Got an electrician in to replace the element, which cost about £150 all told - but when I saw him do it I reckon I could have done it myself.

Anyway, it's just gone again, 3 years later - same situation, same gradual distortion of the element in exactly the same way. Does anyone know why this might be happening? The distortion suggests that the extreme heat is causing the metal to weaken but aren't grill elements supposed to be able to cope with that? Does anyone know if this Bosch model - HBN131251B - is prone to this? Am wondering if it's just better to buy a decent new oven instead of replacing this element and have the same thing happen again in three years or so.

Any advice greatly appreciated - thanks!

 

[Diyisfun]

It may be that the element is not being supported, as originally designed.
The manufacture would have done extensive testing of the element & its support.
Changing elements are pretty simple for most diyers.
As you watched the electrician change the last one, you will know if it was removed from within the grill or he had to do it from the back.
If you do it yourself, you may find the wire at the terminals has gone brittle & may need re-crimping.

 

[bobnotthe builder]

Thanks for this - yes I can do it myself just a bit annoyed at having to do it again. As for the support and the manufacturer's testing the fact that it's gone in exactly the same way suggests it's not a support fault as this wasn't mentioned by the Bosch technician originally. Just wondered if this is a usual kind of problem - 3 years doesn't sound too long.

Thanks

 

[kbdiy]

Do you line the grill pan with foil by any chance?

 

[bobnotthe builder]

oops....er...yes!

 

[bobnotthe builder]

Is that the reason it's overheating? Is that a common thing?

 

[kbdiy]

In a word - yes!

Reflecting the heat back up to the element. If you look in all the manufacturers' instructions they explicitly state NOT to line the grill pan with foil.

You can now look forward to a long-life grill element

 

[ban-all-sheds]

oops....er...yes!

If you want to line the pan for ease of cleaning get some of that silicone sheet sold for the purpose.

However....

In a word - yes!

Reflecting the heat back up to the element. If you look in all the manufacturers' instructions they explicitly state NOT to line the grill pan with foil.

Grill elements get so hot that they glow.

I really struggle to understand the mechanism by which some heat reflected back would raise the temperature of the element by so much that it gets damaged.

 

[kbdiy]

I really struggle to understand the mechanism by which some heat reflected back would raise the temperature of the element by so much that it gets damaged.

Give it another 3 yrs without the foil lining and we'll find out for sure

 

[Diyisfun]

@Ban, isn't that why electric fires have a chrome reflector behind the element?

 

[ban-all-sheds]

That surely is to direct the IR radiation forwards?

 

[JohnW2]

Grill elements get so hot that they glow. ... I really struggle to understand the mechanism by which some heat reflected back would raise the temperature of the element by so much that it gets damaged.

FWIW, I struggle similarly.

Kind Regards, John

 

[kbdiy]

Just repeating what all the manufacturers put in their instructions - and here's the thing - even the gas cookers.

Go figure that!

 

[JohnW2]

Just repeating what all the manufacturers put in their instructions - and here's the thing - even the gas cookers. Go figure that!

Do they actually say the the reason for not using foil is the one you suggest? Do they also say that one should not use 'shiny' grill pans? Maybe they're saying it for some other reason?

Kind Regards, John

 

[planenut]

I always lay perforated foil on my grill pan to allow fat to drain below, been doing that for fourteen years with no ill effects.