"Bob Watkinson" wrote in message
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"Stephen Dawson" wrote in message
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"Bob Watkinson" wrote in message
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"Stephen Dawson" wrote in message
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"Sparks" wrote in message
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wrote in message
oups.com...
A report on a house I'm buying says there "is no evidence of
equipotential earth bonding" of the incoming gas supply to the
boiler.
I have also been told it needs an electrician to correct this.


What exactly does equipotential earth bonding mean, and how important
is it to have it?


It is a cross earthling of metal objects (pipes in this example)

At the boiler, all the pipes should be connected to each other with
earth cables and clamps, then at lease a 10mm cable sent back to the
main earth terminal (in or near the consumer unit). By what you have
posted, it looks like the gas pipe has been left out of this (It is
very easy to rectify with an earth clamp and a piece of 10mm earth
cable).

Is for how important, it is required by the regs, but hasn't always
been.

Sparks...


Out of interest what reqstates the above??

547-02 covers most of it including table 54H. On Site Guide fills in the
gaps


Can I refer you all to OSG (brown Cover) Page 25 Section 4.5, no mention
there of the need for supplementary bonding of a boiler unless it is in a
special location.

What I beleive from the OP is that the main bond is missing and should be
connected within 600mm o the entry of the gas supply to the property.

The is no reason or reg that says, that I am aware of, that you must
cross bond a boiler.

If some one can point me to it the I will stand corrected.

I'm not with you. 547-02 is the reg that covers it. There is a great deal
in the regs that don't appear in the OSG hence the difference in the size
of the two volumes.


No it does not 547-02 covers main equipotentil bonding condustors, not
cross bonding at boilers. A with regard to a great deal in the regs I have
BS7671 in front of me, as is the OSG and all the guidance notes plus other
forms of reference.

So at the moment I am still of the opinion you do not need to bond the
boiler.