Main Earthing

[matt.leung]

Hi,

I am having to deal with a situation where the main gas pipe is being used as an earth for a TT system. From the consumer unit there is a 16mm conductor connecting to a MET block, and then another 16mm cable leading off to the main gas supply under the stairs.

There is a 16mm earth cable connecting the gas meter out side the building which leads to an earth electrode spike....

I have read that metal water pipes can be used as an earth electrode under the new 17th edition. The thing is that the gas pipe makes contact with the water pipes when they enter the boiler etc.....

would this pass a NICEIC inspection?

many thanks

M

 

[green-hornet]

It would definately not!

You can not use a service pipe for main earthing.

The earth rod should ideally be connected directly to the met, from there the bonding should go to the gas and to the water,with regard to metal water pipes being used as an earth electrode under the 17th edition, some one is pulling you leg. There is no such provision.

Where service pipes "touch" this should never be accepted as a good or sound connection.

 

[seajayess]

You can use a water pipe for the Earth connection but it has to be a private water pipe ie your own well and labeled so it is not removed not ideal but within regulations, you cannot use the water pipe that is supplied by the water authority. And no you cannot use the gas supply this should have its own bonding conductor 10mm CJS

 

[binky]

. And no you cannot use the gas supply this should have its own bonding conductor 10mm CJS

6mm for TT minimum csa

 

[grandad]

from the regs

View attachment 116