I am putting in a new kitchen, at the moment there are two double sockets, one single socket and a single oven, on its own 30A ring. The extractor is fed from a drop from the upstairs ring. What I want to do is extend the kitchen ring and put in a fused socket for the extractor, (junction box for the old extractor feed to put the upstairs ring back to how it was), a fused socket for the fridge/freezer,and one for the washing machine and hob. I also have a spare 16A fuse in the consumer unit, if I replace this with a 30A mcb will it be OK for a new double oven? Any help would be appreciated.