Hi,
These are the symptoms of a faulty fan oven element. Basically the oven appears to work ok just not heating up? They are available from us here:
http://www.ukapplianceparts.com/elements.asp?search_fd0=Fan%20Oven%20Element&search_fd5=B1451
POWER OFF BEFORE REPAIR
Fitting is straightforward - just a matter of removing the rear plate from within the fan (2/4 screws). This will expose the element itself which will be held in place by 3 screws. When these have been removed carefully remove the element and disconnect the wires attached noting their positions. You may see visual signs that the element is at fault i.e blowing, splitting, burning etc. but not always.
Lee., December 2006