UK- Earth clamps on domestic boiler piping.

[SimonW]

Dear All,

Does anyone know why on a boiler installation all the pipes are daisy chained to each other via eath clamps, finally connecting to earth.

I ask this because every boiler that has been installed in our houses, not one has this arrangement, yet my neighbours does.

Why is there the need for this... is it dangerous without?..

Regards,

 

[Nigel Goodwin]

It's simply a later regulation - one reason is the introduction of plastic pipes, previously all pipes were copper, so all were nicely connected to each other. Now, some may be copper, and some plastic, so it's possible that some sections of copper pipe could be lacking an earth connection.

As for 'dangerous', like all earthing schemes they decrease some possible dangers, but increase others - if your's isn't bonded, then there's no need to do it unless you want to.

I've recently had new central heating (last November) and I don't think they earth bonded everything? (I'll have to look), but they used all copper piping, no plastic at all.

 

[ericgibbs]

hi,

Like Nigel I have a new central heating system installed recently.

All the heating distribution pipe copper piping has been bonded to the incoming 'rising' domestic water pipe.

I would recommend that all water pipes and fittings be grounded.
The local electricity authority will check out the system for you, there may be a charge for doing the test. But its well worth it.

 

[picasm]

It is a safety precaution that is covered by the building regulations document "Part P" downloadable from:
https://www.electro-tech-online.com/custompdfs/2007/03/BR_PDF_ADP_2006.pdf

Basically all gas and water pipes should be bonded and connected to the main earthing point for the house.
It is particullary important to bond all the pipework in the bathroom.

I don't think every radiator pipe has to be bonded though as long as the main boiler pipes and all bathroom pipes are done.

Also the gas pipe going to the gas meter should be bonded close to the meter. I think this is a precaution required by the gas companies.

 

[Sceadwian]

Just hope that some uneducated plumber doesn't use the neutral line of the power system as a ground, or worse. The people that owned the building previous to us where I work at had somehow managed to wire the buildings steam system to the HOT line of a 120V branch. By some freak of wireing and ignorance this didn't instantly blow anything up so my boss has told me stories of having to be very careful about what you touch until they got a real electrician in to fix things. Luckily they didn't manage to kill anyone.

 

[Hero999]

If you've got two copper pipes with a plastic section separating them, then either connect the two copper pipes together or earth them both separately. Luckilly your boiler is probably earthed though you never know, so it's better to be safe than sorry.

 

[jbelectric777]

where they use plastic main domestic from the street into the dwelling it is a requirement to bond all metallic piping and other like systems. bonding simply means to connect so it is grounded and can trip a circuit breaker or ground fault breaker/outlet... and it is very important. when you have plastic entering from the street it's not a ground electrode so (2) made rod or pipe electrodes must be driven in the ground/earth outside not less than 6 feet apart and bonded to the neutral, if the water pipe is metal from the street it is considered an effective ground electrode and only (1) supplement made electrode needs to be installed outside. the bottom line is if the piping became energized for any reason the circuit can trip before someone can be touching it not knowing it's energized and be shocked if their body found a ground path. (such as in a basement where it's damp) also it's one of the most important things on the inspectors list to check (i am one) and can be found in the codebook article 250 grounding & bonding 2005 NEC