supplementary bonding bathroom

[darren bergin]

If my combination boiler has got cross bonding ie mains water, gas, hot water, flow and return all cross bonded
surely there is no need for supplementary bonding of bathroom radiators .. when it has already been done at the boiler

am i right in assuming this?
thanks

 

[Taylortwocities]

What else do you have in the bathroom? shaver point, lights, heater, shower. All need supp bonding.
See here: //wiki.diynot.com/electrics:sp...rooms_and_supplementary_equipotential_bonding

 

[ColJack]

it also depends on the distance from the boiler..

copper pipes have resistance like a cable
too far away from the cross bonding might see a high enough resistance between 2 pipes to make the touch voltage between them dangerous in the event of a fault..

 

[darren bergin]

there is only a electric shower in bathroom which has a seperate earth cable of its own run from consumer unit..
so cross bonding at the boiler i assume would be ok and no need to bond rads in bathroom????

 

[Taylortwocities]

You need to bond the earth cable of the shower to H&C pipes, bath taps & drain too if it is metal and also the ch pipes at or near the radiator.

 

[dingbat]

You need to test to confirm whether or not you have extraneous conductive parts. You need to test whether or not these parts are already bonded via the pipework. You need to bond between the protective conductor terminals of circuits in the zones. Then you make whatever supplementary bonds are necessary between extraneous and exposed conductive parts.

If you don't verify, by testing, what does and does not need bonding you may inadvertently introduce earth fault paths that did not exist before.

 

[darren bergin]

so if you have to bond at these points as stated

What is the point of bonding at boiler also???

 

[EdwardCurrent]

Hello
Because supplementary bonding is required within certain locations. ie bathroom.
Every circuit that is within your bathroom must have the same 'earth', along with any conductive part.
Does the earth from your shower link up to the pipework within the bathroom ??
If the boiler is situated in an airing cupboard adjacent to the bathroom , then I do believe that your clamps etc can be fitted there.
I hope this is of some help.
Ed.

I have cross bonded pipework at a boiler before just to be sure, although it may not be required I always think that it is better to be looking at something, rather than looking for something.

I believe that you have recently had your consumer unit changed ? Have the test sheets noted that your supp bonding is not up to scratch ??

 

[dingbat]

so if you have to bond at these points as stated

What is the point of bonding at boiler also???

If everything is bonded at the boiler and the boiler is close enough to the bathroom then your extraneous parts may already be bonded. But the only way you'll know is if you test between every point in the bathroom, looking for a continuity reading beow 0.05 Ohms.

You'll still need to connect between the circuits and the extraneous conductive parts in the bathroom zones.

Bonding at the boiler? It can be useful if, as EdC says, the boiler is in the airing cupboard, but more likely it's been done because of a misinterpetation of the wiring regs [601-04-01 and 413-02-02] or a handed-down, mythical CORGI reg.