I remain very doubtful about the utility of such appliances if used for wet central heating which most are.

They combine the worst points of gas central heating, leaks, single point of failure, frost damage, losses from pipes with the high unit cost of electricity.

Electric wet central heating CAN be viable but only with thermal storage in a large hot water tank, heated of peak, and NOT via an “on demand” electric boiler.

A modern and super insulated homes should not need wet central heating.

If however the customer is determined that they want one, then I agree that a dedicated switch fuse is far preferable to a long hour 50 amp load on a domestic consumer unit.

I would select a 100 amp switch fuse, fitted with a 63 amp fuse. Double check that the boiler requires only a SINGLE supply, some require several smaller supplies, one for each element.

I remain very doubtful about the utility of such appliances if used for wet central heating which most are.

They combine the worst points of gas central heating, leaks, single point of failure, frost damage, losses from pipes with the high unit cost of electricity.

Electric wet central heating CAN be viable but only with thermal storage in a large hot water tank, heated of peak, and NOT via an “on demand” electric boiler.

A modern and super insulated homes should not need wet central heating.

If however the customer is determined that they want one, then I agree that a dedicated switch fuse is far preferable to a long hour 50 amp load on a domestic consumer unit.

I would select a 100 amp switch fuse, fitted with a 63 amp fuse. Double check that the boiler requires only a SINGLE supply, some require several smaller supplies, one for each element.