The main (fan) oven causes the supply ELCB to trip as it warms up. It is highly likely that all that is required is to replace the fan oven element from espares for £9.80. If I were 10 years younger I'd do it myself, but the wife wants a new oven anyway. The new one comes Tuesday 11th so it will be taken to scrap if not taken before then.
For photo see:
Zanussi ZDQ595W built in double oven needs repair 88 cm Ht (Welwyn Garden City AL8)
This post has been withdrawn.