I have an electric shower in my house that has worked fine since installed in 2004 but I read something about RCD’s recently, now I am paranoid its all wrong. So advice required on this installation….

9.5Kw shower > 10mm cable > Double pole switch > 10mm cable > 40amp(poss 45 not sure at work currently) MCB on consumer board.

Does that sound right, obviously this was all pre Part P regs?.

nothing wrong with that, what’s your concern?

That’s clearly inadequate and you need a rewire immediately.

It could be a child’s face next time

Well I overheard a sparky doing some work at my workplace talking about shower installations etc and mentioning that the circuit should have a RCD in it , which mine does not. Now on a bit of researching I see the new regs state you do indeed need an RCD from my understanding of it . Just become paranoid about it is all, as its water/electrickery etc.

If it is a NEW installation, this might be true. if it is an existing installation then it is what it is. We’ve got an old style Wylex wired consumer unit that has our shower wired to it.

You could get the breaker replaced with an RCBO if you really are paranoid. However you might then be getting into a situation where you have to change other things to meet current regs because you’ve undertaken work on that circuit. I’d just keep a pair of heavy duty marigolds in the shower for turning it on an off.

Id just live safe in the knowledge that your most likely safer than a large proportion of the uk housing stock.

New regs don’t apply to existing installations.
Rcd’s are worth the effort/expense though and you could fit one between the meter and your consumer unit that will protect the whole installation without having to alter qny circuits.

Rcd’s are worth the effort/expense though and you could fit one between the meter and your consumer unit that will protect the whole installation without having to alter qny circuits.

As I understand it your lights need to be on a separate rcd to your power so that might not be possible.

i’m an electrician and for extra safety a 30 Ma RCD would be better but you cant fail it as it meets old regs ! you can fail it just because its not to the latest regs .

That should be RCD protected. Are you sure that the main incoming switch on the consumer unit isn’t an RCD? if it is the whole place is RCD protected.

RCD incomer

Board with DP switch incomer

Recommended and good practice but it’s not compulsory. For example, TT earthing systems require an rcd to be used this way to comply with bs 7671 iee wiring regs.

oh and I wouldnt have one rcd covering the whole installation and you get nuisance tripping which is a pain in the arse !

oh and I wouldnt have one rcd covering the whole installation and you get nuisance tripping which is a pain in the arse !

Agreed. Better than 9.5kw on an MCB and DP incomer though.

TT systems which have a rcd covering the whole system were only 100 ma not 30ma rcds

just using the image as a guide.

Ive got twin rcds(5 each way) on incoming power similar to old gits photo – no nuisence tripping here . Possibly a fault some where as oppose to nuisence tripping no ?( not a spark )

Edit its this http://www.discount-electrical.co.uk/product.php/4166/wylex-nhiss5504-nh-series-insulated-5—5-way-twin-rcd-split-load-consumer-unit-with-100a-switch-disconnector-isolator—2-x-80a-30ma-rccbs

Thanks all for the input. Its an installation that is now nearly 10yrs old with no faults so far. The consumer unit is a Wylex old type. The mcb for the shower is a modern replacement that fits old wylex. Seems reading your comments its all good.

That’s a split load board, 2 x RCD’s and 1 x DP incomer. Those boards are generally configurable.