Adding shower circuit

[Martin Pentreath]

My CU has no spare ways, but I'm putting in an electric shower. I happened to have one of these lying about:

was going cheap at B&Q a few months ago.

Can this be installed alongside the existing CU to provide for the shower circuit? If so how are the connections made to "piggy back" it? The cable to the 9.5kw shower (which is only about two metres from the CU) is 10mm stuff but this is a 63A unit, so surely it needs some further protection in the form of an MCB?

I think it's time to call out an electrician, but I'd like to know what's what before I do.

[gort]

O

Normally the meter tails are split via a henley block, rather like a large junction box.One set goes to the existing cu and the others go to the shower cu. You really need a RCD & MCB combined enclosure, virtually a 2 way cu as you suspect.

Dave

This is the Screwfix block

the Screwfix shower enclosure

[Owain]

Not on its own, no.

The meter tails are split using Henley blocks like

The cable to the 9.5kw shower (which is only about two metres from the

Yes, it needs an MCB. That unit is an RCD which does not provide any overload protection. You'd be better with a combined unit like one of these

will also need a DP shower isolator switch (pull-cord) near the shower, pay attention to the bonding in your bathroom, and if you care to, Part Pee.

Owain

[David Hansen]

On 19 Jul 2006 02:10:03 -0700 someone who may be "Martin Pentreath" wrote this:-

To add to what has already been said. Do you see a need for any more circuits than the shower one? If so then it may be worth getting a consumer unit fitted that has a few spare ways. Getting something a little larger and leaving part of it spare is more effective than constantly adding small things. You would then wire the shower via the RCD unit you already have.

If you are certain that all you want is a shower then you should be able to find an enclosure that will take the RCD unit you already have, along with a fuse or MCB to provide overcurrent protection. You would then discard the enclosure you already have. However, I would want to look at short circuit currents and a few other things before connecting the unit in such an arrangement.

[Martin Pentreath]

Many thanks for helpful advice. As what I have isn't much use on its own I think I'll follow David's suggestion and just upgrade the CU.