Three weeks ago I carried out a rewire but had to return to complete several items after a new combi boiler had been fitted and the old system removed. Upon my return I thought I would have a look at what had been done by British Gas as they were supplying the whole package. I was surprised to find no cross bonding carried out at all, the heating engineers I work for always ask for this. The client was having a few teething problems with the system and a British Gas installer turned up to rectify so I asked him their policy about cross bonding on a combi boiler system. He replied that it was not now required, who is correct BG or my other Gas Safety registered contacts. Thoughts please.

i always used to bond flow and return ,but if you think about it there is an earth in the flex which attaches to chassis which attaches to all copper pipework so why bother? but this would only apply to domestic as if i recall comercial /industrial should have a main bond to all heating and ventilation systems ,but i may be wrong:
davy

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just because i'm paranoid doesn't mean theyre not out to get me

Well you need main equipotential bonding in place - but the practice of festooning the place with little curly wurly pigtails of green and yellow is as pointless today as when it emerged during the 15th.

When you consider that most of the pipe work connects to big metallic elements within the boiler then perhaps thats no suprise

Regards

OMS

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Failure is always an option

I did see some information on that a while back and I think the idea now was that cross-bonding was only required if the boiler was in the bathroom.

regards

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"Take nothing but a picture,
leave nothing but footprints!"
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"Oh! The drama of it all."
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"You can throw all the philosophy you like at the problem, but at the end of the day it's just basic electrical theory!"
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It was my under stading that supplemenrty bonding may not be requiered porviding that the pipe work in question is adequatly connected to the main bonding.

Talking to a corgi plumber today - they have been told not to do it now!!!

Im gas safe registered and no ones told me not to, think that was a grape vine thing

MrAmps I would i would take no notice of the corgi plumber you spoke to as the governing body is now gas safe.

Big red book says - Supplementary NOT required providing ALL circuits meet the disconnection times and Main Protective Bonding Conductors are present and to the required size.

Isn't there a case for saying that the regs require us to follow manufacturers instructions
If the boiler maual calls for bonding,thats what has to be done
If there is no such instruction,the decision is to comply with the regs

phillron, what page number are you looking at?

Im not looking at books or pages,its just emerging out of my head

If I'm incorrect,someone will let me know pretty sharpish I reckon

lol, i'll have a quick peek in the morning ;-)

I have never really seen the point of this type bonding practice; I personally feel that it is a waste cable. The only time I would install Supplementary bonding to a boiler system, is if it was fitted in a special location, i.e. a bathroom at the time of the 16th edition or if I could not meet all the requirements of BS7671:2008 as it stands now with RCDs for protection. But we must make sure that all main protective bonding to water and gas services are in place before carrying out any work.