Immersion Heater Wiring

As part of my central heating refit, I am having a new and relocated hot water tank with economy 7 and boost immersion heater elements. I plan to feed these via a Horstmann electronic timer.

The circuit will have a dedicated 16A MCB (is the voting for RCD protection or not?)

What are the requirements for further protection? I can't see the logic in having a separate fused outlet for each element, but local isolators at the point where the high temperature flexible terminates seems sensible. Should I fit a fused spur unit upstream of the timer instead?

Chris

The tank will be in the integral garage, so for convenience I want the controller in the pantry, about 3 metres away, as the cable runs. Max load is indeed 3 kW, as the controller ensures the two elements cannot be in use simultaneously.

Pretty lightweight on those aspects. I'm not sure exactly what the regs require.

Chris

On Fri, 09 Jul 2004 19:59:27 GMT, Chris J Dixon strung together this:

IIRC the Horstmann timers have integral fuses so a DP switch feeding the timer would suffice. The immersion heaters themselves will need a DP switch each, located near to the tank.

In message , Lurch writes

AKA pcb track

I'm not so sure you're right there

On Wed, 14 Jul 2004 21:44:11 GMT, raden strung together this:

Well, it was a while since I fitted one, I've got six in the garage but can't be arsed to check at the moment. Might be worth the OP just confirming the need for a fuse, or not, before installing.