The oven is a Diplomat Select 920 and was here when we moved in two and a
half years ago. so we have no idea how old this oven is.
Last year it started emitting a weird chemical smell which is worse at
times, yet not so bad at others. It's quite disturbing as i feel it almost
smells 'toxic' and I don't want the food contaminated.

Any ideas, other than to pay a fortune to call out an engineer who will
probably tell us we need something replaced? Apart from the bulb which has
gone and the awful smell the oven works fine.