main bonding to gas bottles

[marky1]

Hi, new to forum so any help appreciated.
I have just looked at an installation where the boiler is fed via x4 gas bottles, where the copper pipe enters the building it only protrudes by a few mm then bends straight into boiler housing, so very little access. do we still need to main bond this gas supply? as customer said previous sparky said no requirement!?

Can someone please clarify

Thanks

 

[johnboy6083]

In this situation, i would box it off, but make it obvious that its a gas pipe ect. This way the chance of touching different potentials is removed.
What about bonding it outside, before it enters the building?

 

[marky1]

luckily the boiler is in a cupboard above worktop, so the chance of touching different potentials is realy limited, but customer doesnt want earth wire or piping on outside of house! just dont want to fall foul of regs & get my a** kicked, il see if any other way of getting round it. Thanks

 

[Geoffsd]

Perhaps previous sparky was right.

Are the bottles on the ground?
How are they connected to the copper pipe?

 

[marky1]

the bottles are standing on concrete, the 4 bottles are then connected together by plastic pipe before being connected to gas valve which in turn connected to copper pipe on outside of house

 

[Dunc]

Test it using a R2 wander lead and your continuity tester. If you get a reading of >20,000ohms (i think that's the value anyway) when testing between the gas pipe and MET then it doesn't need bonding as it's not classed as being a extraneous conductive part. Chances are if the bottles are sat on slabs and not on grass or mud it won't need bonding.

 

[marky1]

would i not be in breech of regs if i didn't bond gas if previous sparky is right? not being funny just asking

 

[marky1]

sorry, ur post came through as i posted mine

 

[marky1]

thanks, il test it and see what my readings are

 

[Geoffsd]

Dunc is correct in what he says about extraneous conductive parts but you would have to disconnect it from the boiler to do the measurement.

As it is only connected to the bottles via plastic pipe it will not need main bonding.

Also if you get a reading less than 0.05Ω this means it is connected to building pipework - via boiler - and won't need supplementary bonding either.


Edit - I should add that the 0.05Ω measurement should also be obtained between the pipe and any other simultaneously touchable metal parts in the room.

 

[Dunc]

Dunc correct in what he says about extraneous conductive parts but you would have to disconnect it from the boiler to do the measurement.

Missed that important bit! Thanks for adding it on. unk:

 

[Geoffsd]

I've also added another bit - read the previous post again.

Also - I didn't mean you should disconnect it from boiler - it's not necessary.