Found it how can I fix it?

[denso13]

Does this not mean that these installed system should be bonded or is my interpretation of that reg incorrect?

The reg is correct but it's for

complying with Chapter 54 shall connect to the main earthing terminal extraneous-conductive-parts including the following:

Which is not supplementary bonding of heating pipes. It means main bonding of gas and water, and other things, but even then only if required.

electrician has bonded all the pipework or is that just a money making exercise and it shouldn't actual be needed?

Yes, not needed. As we always say on here, follow the regulations. Next time an electrician does it you should ask what reg covers it. There are none.

 

[JohnW2]

@ johnw2 As suggested this all came out of whether it could be one reason why copper pipework was pinholing and whether plumbers should know about bonding or not.

I very much doubt that it's anything to do with bonding (or anything else electrical). However, as I said, IF pin-holing can be the result of currents flowing in metal pipes (I haven't got a clue!), then bonding wold, if anything, sometimes make that more likely.

I've personally experienced pin-holing twice in my house, both in 15mm copper pipe, once about 15 years after new pipe had been installed and the other after 25-30 years. I can't remember which but one was carrying DHW (from a vented cylinder) and the other 'mains' cold water. In both cases we suddenly became aware of multiple simultaneous pin-holes. I've always tended to assume that such events were due to manufacturing defects, but I haven't really got a clue. We are in a very hard water area, so that might be relevant?

I am not sure then why so many bodies seem to specify about bonding and about how important it can be when it comes to domestic installations? As suggested it is still taught as part of the tech certs for plumbing. TB102 also ask for bonding for gas supplies close to the meter. Hence why asking the questions around when and where is bonding required according to the electricians.

The important aspects of main boding are discussed below. Unfortunately, some very iffy (bad?), and persistent, wording of a reg in BS7671 about bonding of gas pipes/meters has led to a lot of confusion. The important point, as below is probably that nothing ever needs main bonding if it does not qualify as an "extraneous-conductive-part"

I also found that BS 7671:2018 Regulation 411.3.1.2 requires that;

“In each installation main protective bonding conductors complying with Chapter 54 shall connect to the main earthing terminal extraneous-conductive-parts including the following:
(i) Water installation pipes
(ii) Gas installation pipes
(iii) Other installation pipework and ducting
(iv) Central heating and air conditioning systems
(v) Exposed metallic structural parts of the building.”
Does this not mean that these installed system should be bonded or is my interpretation of that reg incorrect?

Your interpretation would presumably be correct if you read and fully understand all of the regulation, including the words I have emboldened. It is NOT saying (i.e. doesn't say) that all those things listed as (i) to (v) always have to be bonded to the MET. Rather, it is saying that "extraneous-conductive-parts" have to be bonded, and gives a list of things [(i) - (v)] which might be extraneous-c-ps. However,to be an extraneous conductive part, it has to be (a) conductive (i.e. usually metal), AND (b) has to enter the property from outside it AND (c) travel underground for some if its route before entering the house (and is not an extraneous-c-p if there is an electrically-insulating section where, or before, it enters the property.

Hence, for example, gas pipes entering a property are NOT extraneous-c-ps (and hence do not require bonding) if the only underground parts of the run are plastic and the transition from plastic to metal occurs above ground level, at or before the point where the pipework enters the property.

It's really little more than 'electrical common sense', which can be supplemented by 'testing'. If something IS an extraneous-c-p, then there will be a measurable path to true earth from it. If there is not such a measurable path to earth, then it is not an extraneous-c-p and therefore does not need main bonding

Why is it also when electricians are brought in to check pipework in domestic situation bonding is one of the areas that is brought up all the time as a requirement with metal pipework? See it happening all the time, I'm back to service the boiler and the electrician has bonded all the pipework or is that just a money making exercise and it shouldn't actual be needed?

An electrician who knows what he/she is doing, and understands what is required (and not required) by current regs should bond anything which needs bonding and not bond things that don't need bonding. I'm sure you could find some who behave differently from that, but you'd have to ask them why!

I presume that one can equally find some plumbers who insist on doing some things that are not actually 'required' by any regs (and not doing some things that are required!) - but no trade or profession is populated only by 'perfect' individuals.

And then bonding is applied @ boiler pipework and the requirement to have gas pipes bonded close to the meter.

That's the confusion I refer to above. Only extraneous-c-pds need bonding.

I appreciate that supplementary bonding may no longer be a necessity but it can still found regularly, again I see it all the time when working, especially with properties with older CU's - that then goes back to my questions in the electrical forum as to what and what isn't actually required.

As you say, there's still a lot of it out there, even though very little of it is required these days. I think much of it probably dates back to the days of the 16th ed. of BS7671 when widespread misunderstanding/misinterpretation of what some fairly badly worded regs said, we saw crazy amounts of totally unnecessary bonding - even of things as silly as window frames and door knobs