Installing an electric shower...

[MFeely88]

Hi all. I'm an apprentice electrician coming to the end of my term, so I'm not just a cowboy DIY'er. I'm installing an electric shower next bank holiday weekend at my mum's house, and I just want to make a checklist of everything I need so that I don't have to nip off anywhere. This is what I've got so far -


Shower
15m x 10mm T+E
10mm Clips
Pull Cord
40A Breaker
Shower Unit (This is the only part I'm not sure about) (http://www.screwfix.com/prods/69659/Electrical-Supplies/Consumer-Units/Volex-Consumer-Units/Volex-Shower-Unit-63A-30mA-RCD-1x50A-MCB?cm_mmc=GoogleBase-_-Datafeed-_-Electrical%20Supplies-_-Volex%20Shower%20Unit%2063A%2030mA%20RCD%201x50A%20MCB)?
Earth Tags
15mm Copper Pipe + All the necessary fixings and joints


Have I missed anything off this list?

 

[securespark]

RCD?

EDIT: Sorry. I did not look at that scrwfix link. When you said showr unit, I thought you meant the actual electric shower unit itself.

In which case, the shower itself..what size is it?

Any gear to do the PEB's?

 

[Adam_151]

First of all, shower circuits are notifiable work, you should either notify the work in advance to your local LABC, or if the company you work for is registered to do domestic electrical work and your boss is willing to supervise your work and sign it off through the company (in the way he would if you were doing this job at work) then that could also be an option.

I trust that you have access to calibrated test equipment?

As to the shower disboard... I'd not advise using volex equipment... is the existing board not suitable to come off, or is full/not suitable (ie old wylex standard board)

What rating is the shower?

Is main bonding upto scratch?, I note as you have BS951 clamps on your list that you plan to install supp bonding?...remember to buy your 4mm earth cable

I'd recommend one of those crabtree round 50A pull switches that you wire on the ceiling and then put the lid on... rather than one of those square ones that you wire and then have to try and fold back into a 47mm pattress

Silicone sealent to go round between the shower unit and the tiles?

Isolating valve for the water?

 

[MFeely88]

First of all, shower circuits are notifiable work, you should either notify the work in advance to your local LABC, or if the company you work for is registered to do domestic electrical work and your boss is willing to supervise your work and sign it off through the company (in the way he would if you were doing this job at work) then that could also be an option.

I trust that you have access to calibrated test equipment?

As to the shower disboard... I'd not advise using volex equipment... is the existing board not suitable to come off, or is full/not suitable (ie old wylex standard board)

What rating is the shower?

Is main bonding upto scratch?, I note as you have BS951 clamps on your list that you plan to install supp bonding?...remember to buy your 4mm earth cable

I'd recommend one of those crabtree round 50A pull switches that you wire on the ceiling and then put the lid on... rather than one of those square ones that you wire and then have to try and fold back into a 47mm pattress

Silicone sealent to go round between the shower unit and the tiles?

Isolating valve for the water?

The shower is 8.5kw. As you say it's notifiable work, does the NIC come under the Competent Persons Scheme? So if my boss did supervise the work, it would be ok?

Test equipment I do have, I have access to an RCD tester, Loop Tester and a Megger. The shower RCD unit was there for me to come out of the mains in a 40A breaker, fitting that shower RCD unit next to the mains and coming out of the RCD unit to the shower. I've got bathroom silicone sealent, but I didn't think of the isolating valve. I'll add that to the list, thanks. I also have 4mm earth.

 

[ElectricDunc]

Silicone sealent to go round between the shower unit and the tiles?

Usually shower manufacturers state that you should not seal round the shower unit when you fit it as a small air gap is required to ensure the shower doesn't over heat. Make sure you do seal your pipe/cable entry if your dropping it down stud work or chasing it in to ensure you don't get water down the back of the tiles when the shower is working.

Supplementary bonding isn't necessarily required if all other circuits in the bathroom are RCD protected but ensure the main equipotential bonds are up to standards. If they are there but undersized you will still have to upgrade them to 10mm.

What make is your current consumer unit? Is it not possible to fit an RCBO?

 

[MFeely88]

What make is your current consumer unit? Is it not possible to fit an RCBO?

I'll have to look again when I go round there later.

 

[ElectricDunc]

If you do find that you can fit an RCBO it'll work out cheaper to do that then buy a whole new consumer unit. One thing to note if you have an old Wylex board (as in timber backed) you cannot install any new cabling direct from that consumer unit as it does not satisfy current regulations. I'm probably teaching you to suck eggs here but i've seen supposedly competent electricians do it no end of times. If the consumer unit isn't up to scratch buy some Henley blocks and some tails and install the new consumer unit as a stand alone unit. Also if it is an old Wylex board with plug in breakers it would be advisable to still install a separate unit as these sort of units aren't good at handling higher loads. They have a tendency to melt when supplying equipment over 32A.

 

[Adam_151]

As stated by others, there is no point comming off the board from a breaker to feed a another board right next to it with an RCD and another breaker.

If the board is capable of taking the shower circuit (free way, and not an old wylex standard with 60A main switch [these have a maximum of 30A per fuseway]), but lacks RCD protection... then either use an RCBO, or fit a separate RCD in a din rail ensloure after the circuit leaves the board

Those shower disboards are designed for if you want to split the tails and supply shower from totally separate board

 

[ban-all-sheds]

Put a flow switch in the water feed to the shower. Even if you don't need it now it could be useful in the future to trigger a fan if you want it to automatically come on when the shower is used.

 

[bernardgreen]

Have I missed anything off this list?

Shower curtain, soap and shampoo holder at suitable height etc if not already there.

Anti slip surface for the bath if it is a shower in a bath.