Main bonding to water pipe.

[danijah]

Good evening all, Can anyone offer any advice as to how i should tackle this slight problem i have. I have to upgrade my main protective bonding conductor to my water pipe (to 10mm), as i will be doing a CU change in the next few days. My current bonding is 6mm and the meter tails are 16mm to my current CU. I can't access the pipe behind the stop cock to get my 10mm and earth tag around it. Its protruding through a stud partision wall with a metal plate around it. Going by BS7671 section 544.1.2 I have to make a connection to the water pipe as near as practicable to the point of entry of that service. And be within 600mm of the meter outlet union if the meter is external. I know that the pipes branch off behind the stud wall because there are two water pipes coming out to the left of the wall, and going to the sink. The regs state that a connection should be made before any branch pipework. Is there a solution to this because i don't really want to start pulling the stud wall down. All replies will be appreciated, thanks.

 

[Zeespark]

What earthing arrangement do you have currently Dani?

AndyGuinness

 

[Theorysparky]

near as practicable is the key... close as you can,,,,but bear in mind if there is continuity from the existing to the cu then leave it in but put 10mm close as you can

whats the earthing arrangement ????

 

[danijah]

TN-C-S.

 

[Theorysparky]

My post stands.....

 

[green-hornet]

The key is, as close as is practical, you are never expected to knock a wall down to bond a pipe. everything you do that you feel is not to regulation you can even put it on your certificates, no assessor would mark you down for doing things correctly.

 

[danijah]

I am not sure whether there is any bonding to the pipe behind the wall but the other two water pipes have been cross bonded with 4mm. The nearest place i could put new 10mm would be on either of the two water pipes to the left of the stop cock. I can't see what else to do.

 

[Nicky Tesla]

is the water fed by a plastic pipe? if so dont worry about it cos its not "earthy" which means no neutral currents will be flowing along it, which is the soul reason for requiring a 10mm cable as opposed to 6mm on a TN-S.

Access is needed to check the existing cable though.

 

[danijah]

No the water is fed from a copper pipe.

 

[Theorysparky]

I am not sure whether there is any bonding to the pipe behind the wall but the other two water pipes have been cross bonded with 4mm. The nearest place i could put new 10mm would be on either of the two water pipes to the left of the stop cock. I can't see what else to do.

if you can get back to the cu from there then thats what i would do mate

As G.H. has said you cannot fix everything to the regs all of the time.

i phoned my helpdesk once with an issue.....the answer suprised me......

 

[NozSpark]

Why do bathroom fitters, kitchen fitters and builders keep on boxing in isolator valves,,, what are you going to do it the valve springs a leak?

As for the bonding, just do it to where you can,,, so long as it's accessible

 

[Nicky Tesla]

so long as it's "practicable"

 

[danijah]

Thanks for the positive feedback guys, I 'll bond as near as reasonably practicable.

 

[shed69]

is the water fed by a plastic pipe? if so dont worry about it cos its not "earthy" which means no neutral currents will be flowing along it, which is the soul reason for requiring a 10mm cable as opposed to 6mm on a TN-S.Access is needed to check the existing cable though.

In the situation of plastic pipe or alcathene then you must test at the point where it goes copper, if it's less than 24000 ohms(I think - open to correction) then it must be bonded, if it's more then it doesn't require bonding... Think about this though, most installations will have cross bonding albeit maybe only at boiler so the chances of it been higher are very low.....

 

[Nicky Tesla]

It will only be low due to the bond at the gas meter ( due to cross bonding at the boiler) and that is already done.

No Probs

 

[davetheglitz]

Is there 10mm bonding to gas already in place, and if so is there a combi boiler where the gas and water is all connected together by a big metal manifold?