Bonding

mateylec · Jan 28, 2011

Hi all. I'm wiring a flat (new installation) there's no gas pipe, water main is plastic and all other pipes were too. Just gone back to second fix and found the boiler cupboard full of copper pipes ! I would have bonded these had I known they were going to be there, do i have to or wil it be ok as everything is RCD protected ?

roukel01 · Jan 28, 2011

onsite guide page 31..... Supplementary bonding is not required to metallic parts supplied by plastic pipes. So you should be ok.

telectrix · Jan 28, 2011

get a long test lead, do an IR test at250v between MET/ CU earth terminal, and the copper pipes. if your reading is over 23kohms, no need for bonding. what fuel is the boiler?

roukel01 · Jan 28, 2011

telectrix said:
get a long test lead, do an IR test at250v between MET/ CU earth terminal, and the copper pipes. if your reading is over 23kohms, no need for bonding. what fuel is the boiler?

I take it you disconnect the boiler first??

ezzzekiel · Jan 28, 2011

the pipes wont be electrically connected to the boiler wiring.

roukel01 · Jan 28, 2011

ezzzekiel said:
the pipes wont be electrically connected to the boiler wiring.

If the pipes are connected to the boiler, then they will be earthed through the boiler supply, so surely you would need to disconnect the supply first, or an Insulation test would be pointless.

telectrix · Jan 28, 2011

roukel01 said:
I take it you disconnect the boiler first??

what for?. testing between pipework, not wiring

ezzzekiel · Jan 28, 2011

testing between the met and the pipes, or any extraneous metalwork and met to identify if supp bonding is required,.

as you said earlier the boiler pipes do not need to be bonded together (although plumbers will argue different as its in there training that it is required)

however if you wanted to provide supp bonding for whatever reason to whatever part but were not sure if it was needed then carrying out an ir between the pipe and a known earth would identify this.

DurhamSparky · Jan 28, 2011

if you bond the pipes you will probably introduce a path for a fault current to cause more damage than good!

leave alone and chill out!

zeljuga · Jan 28, 2011

Hi there. Imagine scenario: Heavy rain outside, boiler flu trough the aloy roof with lead flashing on flue. Copper guttering, and Tv antena cable passing close bay all the way down to the ground. Bonding opinion.!!!???

telectrix · Jan 28, 2011

copper guttering, when there's pikeys?

Deleted member 9648 · Jan 28, 2011

If there are no extraneous parts that require main bonding....and the boiler is not in a special location as defined in the BRB....there is no requirement to supplementary bond the pipes...But...if copper pipes from the boiler enter a special location and the 3 conditions to omit supplementary bonding are not met,the pipes will require supplementary bonding at the point of entry to the special location...or....if the pipes are electrically continuous this may be more conveniently installed at the boiler!

mateylec · Jan 28, 2011

Thanks chaps, Wirepuller, very concise ! that does it for me. The boiler is in a cupboard which is in a bathroom and there's a towel rail plumbed through the wall of the cupboard. It's an electric boiler btw

mateylec · Jan 28, 2011

The boiler is electric

Deleted member 9648 · Jan 28, 2011

mateylec said:
The boiler is electric

Makes no difference to bonding requirements.

Engineer54 · Jan 30, 2011

mateylec said:
The boiler is electric

Do you mean, an immersion heater?? ...Or a pukka electric boiler, which are very rarely seen in a domestic installation??

malcolmsanford · Jan 30, 2011

Engineer54 said:
Do you mean, an immersion heater?? ...Or a pukka electric boiler, which are very rarely seen in a domestic installation??

No mate with our gas running out quite a lot of new builds are now having to use 10KW CH boilers. Link below

Thermaflow TH9/210U 10kw High Efficiency Electric Combi Boiler

Engineer54 · Jan 30, 2011

malcolmsanford said:
No mate with our gas running out quite a lot of new builds are now having to use 10KW CH boilers. Link below

Thermaflow TH9/210U 10kw High Efficiency Electric Combi Boiler

Thanks for that malcolmsanford, haven't worked in the UK for a number of years now and this was a new one on me ...lol!!

To be honest, with one of these 13KW beasties tucked away in the bathroom cupboard, i'd be very inclined to cross bond all the bathroom pipework, no matter what the Reg's requires. Relying on an RCD not to fail, is not my idea of safety, ...not for my family anyway... lol!!!

Hell of an initial outlay, and i'm not convinced these boilers are going to be as cost effective as they state, as your most certainly going to be using a good deal of ''On Peak'' power as well as the off peak, especially with the weather you get in the UK, Summer and Winter!! ....lol!!!

kmcgold · Jan 31, 2011

check with the gas fitter some boilers must have copper pipe for a short distance before plastic
can be connected

telectrix · Jan 31, 2011

kmcgold said:
check with the gas fitter some boilers must have copper pipe for a short distance before plastic
can be connected

boiler is ELECTRIC

jmtisme · Jan 31, 2011

Engineer54 said:
Thanks for that malcolmsanford, haven't worked in the UK for a number of years now and this was a new one on me ...lol!!

To be honest, with one of these 13KW beasties tucked away in the bathroom cupboard, i'd be very inclined to cross bond all the bathroom pipework, no matter what the Reg's requires. Relying on an RCD not to fail, is not my idea of safety, ...not for my family anyway... lol!!!

Hell of an initial outlay, and i'm not convinced these boilers are going to be as cost effective as they state, as your most certainly going to be using a good deal of ''On Peak'' power as well as the off peak, especially with the weather you get in the UK, Summer and Winter!! ....lol!!!

Some energy suppliers will give you a discounted tariff if no mains gas in your area