Equipotential Bonding... Again! Ask questions and find answers to many subjects relating to electrics and electrical work

[joe4542]

Hi,
Sorry if I'm asking the same question that has been asked before, but I do find this quite a confusing subject and there are many differing answers . :shock:
I'm re-doing my kitchen and have moved some of the pipework but need to check the Earthing arrangements - I understand that the Kitchen itself does not normally need supplementary bonding, but just want your views on the current setup.
It's an upstairs maisonette, with some fairly old wiring down at the CU, but it does look like some extra earths were fitted not so long ago. I think I need to do the main 10mm earth to the gas meter down in the CU cupboard since I cannot see any in the cupboard, and the new gas meter we had fitted last month got a sticker from the fitter saying he cannot see any Equipotential bonding to our pipes - buts thats another part.:?
Our water main - its a lead pipe coming into middle of house from downstairs flat, which I've joined downstairs to copper pipe via a 'Lead-Loc'. This copper pipe runs under the kitchen floor to the back of the house, where it comes out of the floor to a new stopcock I've fitted. Since this it the first accessible point in the flat - [b]This is where I would attach my 10mm earth which runs up from the CU ? [/b]

This 10mm earth which was previously attached to some of the pipes, was also run along all 5 of my combi boiler pipes - CH FLOW, DHW, GAS SUPPLY, MAINS WATER, CH RETURN.

Would I be best to do the same and run the 10mm Earth that I attach straight by the stopcock, over to the 5 boiler pipes, even tho one is already then attached (MAINS WATER)? ... OR would it be ok to cross link the 5 pipes together with 4mm Earth (using the Combi Mains in for Earth).
With the earth wire - I'm not sure my 10mm main will be long enough to reach - is it OK to join with another piece or what?? Would normal Metal Earth block be OK for this?

Does everything above make sense to you - hope so...and that you can try give me some advice - there are so many different threads around that I dunno what way to go!!

Thanks in advance! :D
Joe

[sparx]

Hi joe, most of what you mention seems ok, & if not visible best to assume gas not bonded!
water main 10mm2 bond should be continuous, but generally accepted as such only if any joint 'permanant' ie not connector block ie crimped thro' using ratchet type crimp tool with solid tube type crimp (not plastic coated vehicle type).
Do not link main bonding 10mm2 earth to equipotential 'cross bonding' at boiler! This is a No -No!
If you look at pipes at boiler most now go thro' a 'gland plate' metalically linking them all together which then has a flex. earth conductor linked to the boilers electrical supply CPC (earth) so in most case no need to further bond.
Lastly if gas & water inlet points are close together it is permitted to link one on to the other as long as @ first point the conductor is 'continuous' as above, regards SPARX

[joe4542]

Sparx, Thanks for the reply.
I think I'll actually be able to use the existing 10mm without having to extend if I'm only linking to the Water main in the kitchen. The Gas pipe downstairs, yes I will want to do that ASAP anyway.

The boiler does have the gland plate that you speak of - onto which all connections run through - but I don't remember seeing a particular earth link, I'm sure the whole chassis would be earthed through the boiler wires anyway, but I'll have a check and may link the pipes under boiler into its CPC separately.

Thanks Again.
Joe