Rosieres Bocuse 4040 Oven & Grill problems

We have had a Rosieres Bocuse 4040 range cooker from new (bought 1996?) and it has served us very well (I can’t tell which precise model it is as there are no markings on the doors, it has no rotissery). However, the left fan oven is now not heating fully (e.g. set to maximum with fan on it only reaches about 180C). the other day the right grill element failed. I’ve seen posts and advice about the grill element which I hope I can replace myself. However, I haven’t so far found any info about the oven problem. Can you tell me whether there is an element failure or perhaps the thermostat has a fault? Can I repair the oven myself?. As far as access is concerned, the cooker has built in cupboard units each side so if the repair/replacement requires any other access than from within the oven,the whole cooker will need to be pulled forward clear of the cupboards. Might I be better finding a suitable engineer/electrician and, if so, do you know of one in the Brighton area. I can’t find one on the site.

Thanks for any help you can offer.

Regards

Peter Stuart