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L

lobello

Much discussed issue this one. Appreciate any comments.

I let a small one bed flat out. Electric only ie no gas.

Year back I had a new CU put in with all circuits on RCD's (RCBO for lighting). Accompanied by an EICR. Registered ECA sparks did the work.

The EICR documents that the mains bonding for the water is in place (connections verified etc) and that there is "presence of supplementary bonding".

My understanding is if a. all circuits on RCD b. disconnection times met and c. mains bonding in place and all pipework linked to this continuously then no supp bonding required under 17th.

My question is would the EICR of investigated/ taken account of any requirement for supp bonding and *thoroughly* checked this ie tested continuity on pipes, ensured that any supp bonding was at least sufficient.

Two concerns I have are:

- The hot and cold pipes into the bathroom have plastic sections where the pipes come up through the concrete floor which may possibly break continuity. The *cold* pipe has two bonding cables that go back into the wall I assume these go to the light and extractor fan which were present when the flat was built. However the *hot* pipe has no bonding or cross link from the cold and comes out from under the bath to the bathroom sink where it is briefly exposed. Since the flat was built an electric shower has been added (with RCD on circuit but I suspect not bonded to any of the pipes). I guess it'd be possible to be holding the shower hose (metal) and touching said hot water pipe. Does the hot pipe in bathroom perhaps need some supp bonding or can I assume the sparky did a continuity test on it?

- In the immersion storage tank cupboard there is an overflow pipe from the plastic cold feeder tank, said pipe is initially plastic after the feeder tank but then 7 foot or so of copper running down into the floor. It isn't linked back by bonding to the mains bonding at the water in or the link across from mains in to hot water pipe at the immersion. Hence this pipe is more than likely not linked into any bonding arrangements. Does the provision of RCD's allow for this or is a link across from the other pipes required?

I could of course go back to the Sparks who fitted the CU and carried out the EICR but a. he's a tad grumpy and defensive and not that clear in any explanations b. cancelled him recently for appliance testing as he's very, very expensive and have heard no word since to say ok all cancelled c. probably already driven him mad with my concerns already! At the same time he was thorough in his EICR on other stuff and seemed more than competent.

thanks in advance.
 
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Not sure why you should be concerned lobello? If all your circuits are RCD'd then supp bondng is not required. From what you've said the spark just made a note that supp bonding, which almost certainly pre-dated you new CU, was present while he was doing his visual. I don't want to be rude but this looks like a case of a little knowledge .... earthing and bonding are not the same thing.
 
Supplementary bonding doesn't always have to be a cable link between pipes. Monoblock taps or mixer taps on a bath will provide the same function. As for whether or not you need supplementary bonding that's another story.
 
Not rude at all Clink, little knowledge indeed...however the question arises from point c. above where the 17th states that supp bonding can be omitted providing all 3 conditions are met, those being:

a. rcd's on all circuits
b. disconnection times met
c. mains bonding in place and *that all extraneous pipes in bathrooms are linked back to this*...ie continuity not broken

With my little knowledge and all due respect I'd suggest your statement that supp bonding is not required with RCd's is simplistic and doesn't take into account the actual conditions where supp bonding can be omitted...point/condition c above may not be met if continuity is broken by the plastic pipes where piping into bathroom comes out of concrete floor.

Or have I got that wrong?

PS: yes the supp bonding in bathroom does predate the EICR.
 
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Supplementary bonding doesn't always have to be a cable link between pipes. Monoblock taps or mixer taps on a bath will provide the same function. As for whether or not you need supplementary bonding that's another story.

In this instance single taps standalone neither mixers or mono blocks. Couldn't see anyway that the supp bonding on the cold pipe could connect with hot pipe in the bathroom.
 
going back to your post #4, point c. extraneous is the key word. just because you have copper pipes in the bathroom does not mean that they are extraneous. for a metal pipe to be considered extraneous, it must have a resistance to the MET of < 23k ohms.
 
going back to your post #4, point c. extraneous is the key word. just because you have copper pipes in the bathroom does not mean that they are extraneous. for a metal pipe to be considered extraneous, it must have a resistance to the MET of < 23k ohms.

Yes kind of understand that, could I assume that is something the spark would consider/test in the EICR?

And would I be right in thinking effectively that means the same as "continuity not broken"?
 
it means that if the resistance to earth is < 23k ohms, then that metallic pipe may be capable of introducing an earth potential ans as such may need to be considered extraneous and bonded.
 
it means that if the resistance to earth is < 23k ohms, then that metallic pipe may be capable of introducing an earth potential ans as such may need to be considered extraneous and bonded.

Ok thanks.
 
Ok so thanks all for replys.

Am still no nearer to answering my questions though!

Anyone can to say:

- am i safe to assume that the sparks will have checked that the hot pipe is not extraneous/has continuity to the met or ought i ask him?

- does the overflow pipe from the plastic feeder tank need bonding?

- if the cold or hot pipe in the bathroom are extraneous/don't have continuity to the met does the supplementary bonding need to also connect upto the the shower?

Thanks again.
 
Ok so thanks all for replys.

Am still no nearer to answering my questions though!

Anyone can to say:

- am i safe to assume that the sparks will have checked that the hot pipe is not extraneous/has continuity to the met or ought i ask him? he's the expert. trust his judgement

- does the overflow pipe from the plastic feeder tank need bonding? no

- if the cold or hot pipe in the bathroom are extraneous/don't have continuity to the met does the supplementary bonding need to also connect upto the the shower? no.

Thanks again.

my thoughts in red.
 
As over cautious as this seems, I have to say it's refreshing to see a landlord so concerned about his tenant's electrical safety. There are so many that don't give a monkeys, you are to be commended for your thorough and conscientious attitude lobello.
 
Referring to the OPs concern about continuity being broken by plastic lengths of pipe -

The purpose of bonding is not to maintain continuity and indeed plastic pipe feeding the basin copper pipes means that these copper pipes must NOT be bonded.
 
Much discussed issue this one. Appreciate any comments.

I let a small one bed flat out. Electric only ie no gas.

Year back I had a new CU put in with all circuits on RCD's (RCBO for lighting). Accompanied by an EICR. Registered ECA sparks did the work.

The EICR documents that the mains bonding for the water is in place (connections verified etc) and that there is "presence of supplementary bonding".

My understanding is if a. all circuits on RCD b. disconnection times met and c. mains bonding in place and all pipework linked to this continuously then no supp bonding required under 17th.

My question is would the EICR of investigated/ taken account of any requirement for supp bonding and *thoroughly* checked this ie tested continuity on pipes, ensured that any supp bonding was at least sufficient.

Two concerns I have are:

- The hot and cold pipes into the bathroom have plastic sections where the pipes come up through the concrete floor which may possibly break continuity. The *cold* pipe has two bonding cables that go back into the wall I assume these go to the light and extractor fan which were present when the flat was built. However the *hot* pipe has no bonding or cross link from the cold and comes out from under the bath to the bathroom sink where it is briefly exposed. Since the flat was built an electric shower has been added (with RCD on circuit but I suspect not bonded to any of the pipes). I guess it'd be possible to be holding the shower hose (metal) and touching said hot water pipe. Does the hot pipe in bathroom perhaps need some supp bonding or can I assume the sparky did a continuity test on it?

- In the immersion storage tank cupboard there is an overflow pipe from the plastic cold feeder tank, said pipe is initially plastic after the feeder tank but then 7 foot or so of copper running down into the floor. It isn't linked back by bonding to the mains bonding at the water in or the link across from mains in to hot water pipe at the immersion. Hence this pipe is more than likely not linked into any bonding arrangements. Does the provision of RCD's allow for this or is a link across from the other pipes required?

I could of course go back to the Sparks who fitted the CU and carried out the EICR but a. he's a tad grumpy and defensive and not that clear in any explanations b. cancelled him recently for appliance testing as he's very, very expensive and have heard no word since to say ok all cancelled c. probably already driven him mad with my concerns already! At the same time he was thorough in his EICR on other stuff and seemed more than competent.

thanks in advance.
eh?...
 
Accompanied by an EIC not an EICR.

The lighting circuit is an RCBO and the other circuits are on RCD. CU - consumer unit.

Beyond that not sure I understand the "eh?"...if above doesn't answer for you what's your point please?

And for info. prior to that work I did have an EICR done that recommended the RCD's etc hence the further work.

 
Referring to the OPs concern about continuity being broken by plastic lengths of pipe -

The purpose of bonding is not to maintain continuity and indeed plastic pipe feeding the basin copper pipes means that these copper pipes must NOT be bonded.

The cold water pipes are in exactly the same scenario (plastic pipe out of concrete floor into copper pipe) and are bonded (supplementarily I think to the extractor and light in the bathroom but for all I know one or both of the green and yellows may go back to the MET).

So if the hot pipe must NOT be bonded then surely it would follow that neither must the cold?

This also to my limited knowledge seems to contradict the 17th recommendation that to omit supp bonding in a bathroom if all pipework is effectively bonded to the MET.

A little knowledge is a dangerous thing for sure...think I have to take the advice of trust the experts judgement - one who did the EICR and the other who did the resultant CU change and accompanying EIC. Both from my understanding have a duty to check both mains and supp bonding are adequate when doing the both the inspection and notifiable work.
 
read what you put then in red..
where doed it mention EIC eh?

Mmmm as I pointed out I typed EICR by mistake rather than EIC, just looking through the paperwork I realised it was an EIC hence marking that up for you. The electrician who did the CU change and provided the "EIC" actually said I'd get another EICR - the two cover pretty much exactly the same ground all be it from different Regulatory bodies - ECA and NIECEC.

Thanks for your input Glenn.
 
No disrespect to you (I would not expect you to) but it is clear that you do not understand the purpose nor application of supplementary bonding.
Unfortunately, nor do a lot of 'electricians'.

The cold water pipes are in exactly the same scenario (plastic pipe out of concrete floor into copper pipe) and are bonded (supplementarily I think to the extractor and light in the bathroom but for all I know one or both of the green and yellows may go back to the MET).
So if the hot pipe must NOT be bonded then surely it would follow that neither must the cold?
From your description, that is correct.

t to omit supp bonding in a bathroom if all pipework is effectively bonded to the MET.
That's the point - it does not say 'all pipework', it says 'all extraneous conductive parts'.

Pipes that are NOT e-c-ps must NOT be bonded.

A little knowledge is a dangerous thing for sure...think I have to take the advice of trust the experts judgement - one who did the EICR and the other who did the resultant CU change and accompanying EIC. Both from my understanding have a duty to check both mains and supp bonding are adequate when doing the both the inspection and notifiable work.
I would not think the CU replacement would involve checking "supplementary bonding was adequate" as none is now required.

The EICR would report on the installation without altering anything.
From what you say it would appear that some doubts should have been raised about the supplementary bonding.
 

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