New electric oven installation

Bought new oven to fit in to existing cupboard space. Found the old one was not wired in properly so intend to put 45amp switch in. Can this be behind the oven inside the cupboard? About 20cm of space - just worried about potential heat on switch.

The switch has to be where you can quickly get at it in an emergency, e.g. fat caught fire; thermostat failed, child got hold of live element; person cleaning it gets a shock from electrical fault and water; or for servicing.

So it must be in plain view; obvious what it is for (labelled if necessary) and not directly above or behind the oven or cooker (so you don't have to lean through the smoke and flames) but to one side (not more than 2 metres).

BTW a typical UK single oven runs at between 10 and 12 Amps, so you will need a circuit fused near that, or else a fused plug and socket. I am assuming that when you say "oven" you mean "oven" and not "cooker".

It is actually impossible to put the switch in an easy access point without dismantling the whole of the kitchen. Oven is in old chimney breast that is surrounded by brick; wire just comes out of wall. Was shocked that the old was connected with terminal block. Not easy to put switch in position of access. Thanks for help anyway.

if you think there's enough heat to affect the switch in the cupboard next to the oven, why do you think we mount these ovens in wooden frames??? the fact is, an oven gives off next to ZERO heat from behind. They are well insulated in order that they CAN be fitted inside wooden cupboards!