You say '..not although everything is working'. Can you check all the functions and tell me what IS working? It is possible that the circular element on the back wall of the oven has blown. The oven fan would still operate in this case, making you think that all is OK. Or the cooling fan, which cools the whole case from the top, might be going, making you think that all in the oven is OK; you can feel the breeze coming out from the grills under the controls. By the way, I've just checked my oven and found that the main fan has jammed!
Jimbo
September 2009
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