Fitting a Shower (Some Q's)

[sg160187]

Hello forum.

I have just been given the task of fitting a shower for an elderly lady. Shower is supplied by customer (8.5kw) I need to run 10mm cable from board to unit (approx 20-25m) connect and test. She has an old wylex board (http://www.cambselectrical.com/blog/wp-content/uploads/2009/03/old-wylex-fusebox-300x182.jpg) I am trying to keep cost down and am wondering the best way to connect at the mains end. The board is protected by an RCD.

Any opinions?
Maybe run tails to a seperate 63a RCD enclosure?

I have quoted £100 for materials plus hourly rate of £15.

 

[ezzzekiel]

cheapest would be from spare way in db to shower in 6mm (depending on calc)
part p

is bonding adequate?
split tails to rcd as stated
10mm (again depending on calc)
isolator
then any plumbing materials

 

[Notsosmart]

Yep seperate shower RCD board incorporating MCB, don't forget to check bonding arrangements. If you can I would possibly look into fitting some plug in breakers for her as well, but they don't seem as cheap as they used to be.

 

[sg160187]

Yep seperate shower RCD board incorporating MCB, don't forget to check bonding arrangements. If you can I would possibly look into fitting some plug in breakers for her as well, but they don't seem as cheap as they used to be.

She is aware that the board needs changing and has said she would liike it done at a later date. It's my mates job but he is going away for the weekend so threw it over to me. She has friends visiting this weekend and needs it done pronto. Thats why spending £40 on RCD + Unit is a cost issue. You say you would fit a seperate MCB in this unit? Is there a problem coming straight off the RCD?

cheapest would be from spare way in db to shower in 6mm (depending on calc)
part p

is bonding adequate?
split tails to rcd as stated
10mm (again depending on calc)
isolator
then any plumbing materials

Its plumbed in and sitting on the wall just needs the electrical side sorting. Will check bonding and cable has to be 10mm. I can use the 16mm tails or do I have to go for 25mm?

Thank you for your responces

 

[Spudnik]

If the CU is protected by a 30mA RCD and not a VO, i would carry on and install, and just note the deviations on the cert.

However, bonding MUST be brought up to date if it needs it, of course depending on earthing arrangements.

 

[ezzzekiel]

providing main fuse is 80a or below 16mm will be fine,
i take it the rcd is protecting the whole installation and at 30ma?
is there a spare way in the db, if so wire into that and fit a plug in mcb to replace the fuse.

 

[sg160187]

Can I purchase these compatible mcb's from my local denmans electrical supplies? I need them for tomorrow and am doing a supply run in the morning.

Also I was going to go for the 45a isolator wall switch instead of the pull switch. Would it still have to be at the correct heights? It is in the main hallway.

Once again cheers for the replys.

 

[chris gray]

haha you've quoted a cost for materials but yet not priced them up?
i threw a load of plug in mcbs away yesterday or id of given you them for an oap

 

[ezzzekiel]

most wholesalers stock them about £10 (a screwfix should be nearby), isolator height is in a bit of confusion at moment (450-1200) personally they still go at top of wall for me same as fan isolators

it should be local to the circuit (unless by hallway you mean next to showeroom

 

[sg160187]

haha you've quoted a cost for materials but yet not priced them up?
i threw a load of plug in mcbs away yesterday or id of given you them for an oap

It's a pretty loose quote which she is aware of. I said around £100 for materials, I went higher than I thought so if it does come to the full £100 it won't look like I'm ripping her off with hidden costs

Cable should be about £50 (20m)
Isolator + back box about £10
Plug in mcb ?
Clips £3
Total £70

Labour costs were on top of the materials. I'm currently trying to establish a good reputation.

How much are the plug in mcb then? Also can I get them from somewhere like Denmans/Screwfix?

 

[sg160187]

most wholesalers stock them about £10 (a screwfix should be nearby), isolator height is in a bit of confusion at moment (450-1200) personally they still go at top of wall for me same as fan isolators

it should be local to the circuit (unless by hallway you mean next to showeroom

Yea the Bathroom access is on the main hall. I'm tempted to put the top of the switch level with the top of the door frame but I don't want her to have trouble turning it on and off.

Cheers for confirming I can pick them up from wholesalers.

 

[chris gray]

Wylex Plug-In MCB from Alert Electrical
that was off a quick google search, just look on the screwfix website.
personally id give a few local wholesalers an early call (remember its saturday) they should stock them.

 

[markharris]

I thought if the shower/ bathroom has rcd protection, then there is not a need for supplementary bonding? Or have I misinterpreted the regs?

 

[ezzzekiel]

not supp bonding, main bonding is still required and should be sized accordingly.
supp bonds ommited if criteria are met

 

[Notsosmart]

Thats why spending £40 on RCD + Unit is a cost issue. You say you would fit a seperate MCB in this unit? Is there a problem coming straight off the RCD?

The Rcd will provide earth fault protection but not over current protection.

If the CU is to be changed at a later date and as it is protected by an rcd (so long as it is 30mA) then I would try to re-arrange the (full) board to create a spare way and wire into this, then fitting as many plug in MCB's as can be afforded.
The 45A isloator switch does not have to be between 450-1200mm (only applies to new build) but as you have rightly stated it needs to be easily accessed by the customer.