redundant water heater circuit - ok for new combi boiler

[WELLY417]

Hi all

Wondering if i need to change anything about an existing water heater circuit before using it to power a new combi boiler? (corgi guy starts monday)
I know i need to fit a 3 amp fused connection unit at he boiler end but not sure about the consumer unit which has a 16a mcb and is on the non rcd protected side of the unit. Do i need to change rcd rating or move to rcd protected? (and if so maybe it would be easier just to run a spur off another existing curcuit with correct rating and protection, unless boilers need their own circuit like immersion heaters?)
Thanks in advance for any help

 

[jj4091]

Your mcb should be fine & better to be RCD protected. If it is easier to fit a new spur then do it that way, but I wouldn't have thought so, if you are competant to work in either area.

 

[sm1thson]

i would be tempted to leave it on the RCD side of the board, theres not much risk of shock from a boiler (as its class 1) but there the pump ages there is a good chance of it tripping an RCD and thus taking your other circuits with it. that's not to say the above post is wrong, it would be good to have it on its own RCBO, just not the same rcd as the other circuits.

if any extra concealed cable needs adding (or moving?) then the new (moved?) cable would need come under the 17th edition (latest regs) and thus require an RCD to give protection if someone puts a nail through it (although cables are to be run in safe zones).