Is it necessary to earth a hot water pipe?

[kendor]

See newly released NIC book "Snags & solutions - earthing & bonding" and you will see that they are adamant that bonding to a sink is NOT required. (Snag 29).

I was actually referring to the pipes but included the whole sentence but as the sink has now been brought into it then still i feel as long as you can get a good reading from the sinktop aswell then agreed you don't have add extra bonding.

 

[plugwash]

so that pipe in the pictures is the gas pipe you mentioned earlier?

the thing below the meter is the service fuse

as there are only 2 wires entering that box it must be a PME install

in this case main bonding is vital and must be at least 10mm with 16mm strongly reccomended my most recs

those cables seem a bit small (hard to tell from a picture though)

personally i would do the following
remove all existing bonding at the kitchen sin and all existing earth wires from the fuseboard

fit a main earth terminal
http://tlc-direct.co.uk/Products/TLEB8.html

run 16mm earth cable from the earth terminal on the service duse unit to your main earth terminal

run 16mm earth cable from the main earth terminal to the gas pipe just after the gas meter

run 16mm earth cable from the main earth terminal to the water pipe as colse as possible to entry to the house

run 2 seperate 10mm cables from the main earth terminal to the CU earth bar (your CU is a wylex standard and the earth bars in them will not take 16mm properly)

 

[ban-all-sheds]

As far as I can make out, the top pic shows the fuse box, with an earth wire coming out left to the gas pipe, and live and neutral (presumably) and earth coming down to the board at the bottom.

The bottom pic shows the live and neutral with the meter (can someone tell me what the grey thing is beneath the meter?);

That's the main supply fuse.

and then an earth cable I'd not noticed before also entering the grey box. The earth wire coming from the fuse box was the one I originally thought went into the wall; but maybe it goes into that grey box?

I'm sure it does - looks like you can wiggle/tug it to confirm, but I can't imagine that it's not the same cable.

This is very good news for you.

Ideally the earth cables from the gas main and the water main should go directly to the main earth terminal on the incoming supply, not via the fusebox.

And talking of the water main, I guess you really should try to find the other end of that earth cable. If you turn off the power and remove the cover from the fusebox, what do you see?

 

[securespark]

Plug

Just to confirm what you are saying:

The bonding connection to the gas pipe should preferably be made at the point of entry into the property if the meter is outside, or within 600mm (if practicable) of the meter outlet union if the meter is inside the property. The connection should be made before any branch pipework, but not onto lead.

The connection to the water main must be made on the CONSUMER'S side of the cock, not at the point of entry. The purpose of main bonding to the water is to protect the consumers pipework. We are not worried about the pipework prior to the cock.

Just looked at your piccys:

From experience and comparison with other cables in the picture, I would say that the main earth from the grey cut-out service fuse and the gas bonding conductor SEEM to be both 16mm2, and your tails (to cu) also look like 16mm2 (double insulated, so are fatter than single insulated earth wire).
Hope this clarifies things for people.

 

[graham365]

And talking of the water main, I guess you really should try to find the other end of that earth cable. If you turn off the power and remove the cover from the fusebox, what do you see?

OK, there's *another* earth cable running upwards from the fusebox; and it disappears through a hole in the breeze block wall. Presumably that's the same cable as the one connected to the copper cold water pipe?

Am I OK now, as far as having the right earthing/bonding goes? And cheers for all the advice, guys. I've learned a lot just from this one thread.

 

[ban-all-sheds]

OK, there's *another* earth cable running upwards from the fusebox; and it disappears through a hole in the breeze block wall. Presumably that's the same cable as the one connected to the copper cold water pipe?

That would seem a reasonable assumption. It would be odd if there was an earth wire leaving the CU, and ending up nowhere, and an earth wire leaving the water pipe and ending up nowhere..

Am I OK now, as far as having the right earthing/bonding goes?

Well - we've yet to deal with the supplementary bonding in the bathroom

But the main stuff is in reasonable shape - it goes via the CU rather than a separate main earthing terminal (MET), but AFAIK that's not a hanging offence.If plug is right about the size of the cables that the fusebox can take then the one running from there to the supply earth isn't as big as it should be (16mm), so you could check that, and if necessary run a 2nd bit of 10mm to the supply earth. Or follow plug's entire plan, but I gess the MET would have to be up high near the CU, or the cable from the water pipe wouldn't reach.

 

[securespark]

FWL had this idea that main bonding should be connected only to MET, not to CU, but then I pointed out that MK (amongst others) have "BONDING" terminals in their CU's, so it must be OK.

 

[plugwash]

thats a newer qylex standard so maybe it does have the space

or maybe (likely) the wire was trimmed to fit the terminals in the earth bar

 

[ban-all-sheds]

FWL had this idea that main bonding should be connected only to MET

That's what the diagrams in the OSG show, but whether that's a regulation or just best practice IHNFI.

 

[securespark]

NNTS!