I assume that the grill is in the top of the oven, they sometimes use the grill element as well as the oven element, to heat the oven, as the grill does not work, could be why it is taking a long time to heat up. Best solution, is to get the element metered with a test meter, probably the grill element gone, but best make sure.
Sometimes, I have had it myself, replacement element, was only about £20 cheaper than a new oven. So new oven got it, especially if you are not fitting it yourself, cost of labour would take it over the cost of a new oven. price them up, plenty of places on the web do elements.
SD, November 2011
