earthing

[Mab40]

Hi

My bungalow has no additional earthing on the sink or bathroom, built in the 60s or sooner i think.
I have no gas boiler as i am solid fuel, all central heating is in plastic pipe,My Question if i install a shower will this need supplementary bonding back to the CU, I will be getting a sparky to connect up but i am doing the dog work myself ie running cable and plumbing just need to know if i need to run earth cable.

 

[SparkyNinja]

Have you had an electrician around to access the existing condition of your installation?

 

[Mab40]

Not yet

 

[Chri5]

With current regs to 17th addition the shower will require an RCD.

Supplementary bonding may not be required if the existing electrics in the bathroom are all on an RCD.

See:-

//www.diynot.com/wiki/electrics:speclcn:supbond17th

//www.diynot.com/wiki/electric...l_bonding:supplementary_equipotential_bonding

 

[Mab40]

Thanks for the info

the only other electric in the bathroom is a light which is on a RCD.
shower was going to be on a 45amp but need to speak to sparky as the shower i have got is 10.5kw which if i do the math gives me 45.65amp.

 

[Taylortwocities]

the only other electric in the bathroom is a light which is on a RCD

Does this mean that you have had a new consumer unit installed recently? Can we see a picture please?

shower was going to be on a 45amp but need to speak to sparky as the shower i have got is 10.5kw which if i do the math gives me 45.65amp.

Your calculation of 10.5KW = 45.65amps is correct if your supply voltage is 230V.

But that is not the important part.
What is the size of the cable from the consumer unit to the shower? What is the route? is it clipped along its length, does it share its route with other cables, is it subject to high temperatures, does it go through thermal inslation?
These are the factors that will determine the size of fuse/mcb. Not the size/rating of the shower.

 

[Spark123]

Showers are still usually marked up with their 240v rating, for example it is more likely a 10.5KW @ 240v and 9.6KW @ 230v unit. You need to check with the manufacturer.
10.5KW sounds better in the sales blurb.