Main bonding gas

[Grayza]

Hi, just looked at a job to replaced a CU in an old bungalow with a detached garage (garage has is own CU). The gas meter/supply is in the garage and currently no visible bonding. My question is where should the gas be bonded and which CU should it be run from or should it be bonded both in the garage and where it enters the bungalow?

Many thanks

 

[loz2754]

IMO, if the gas is bonded in the house (10mm) and there are no branches , then the gas pipe in the garage is also bonded by vitue of the conductivity of the pipe itself. a continuity test from garage gas to MET would prove. a 22mm copper pipe has less resistance per metre than 10mm cable. tin hat on.

Perhaps, but then it could be argued that the gas pipe has become part of the bonding conductor, which we know is prohibited.

Edit: Or am I just being silly now ??

 

[Mike Johnson]

Hi, just looked at a job to replaced a CU in an old bungalow with a detached garage (garage has is own CU). The gas meter/supply is in the garage and currently no visible bonding. My question is where should the gas be bonded and which CU should it be run from or should it be bonded both in the garage and where it enters the bungalow?

Many thanks

As far as I know the gas supply should be bonded back to the MET within 600mm of the meter , irrespective of how many CU's there are, it's the MET and gas meter that's important.

 

[farmerspark]

Fairly sure there's the words "where practicable" included in the reg wording.

So in my head if it's not possible to get a 10mm to the garage it is acceptable to bond in the bungalow.

Tin hat on

 

[Mike Johnson]

Fairly sure there's the words "where practicable" included in the reg wording.

So in my head if it's not possible to get a 10mm to the garage it is acceptable to bond in the bungalow.

Tin hat on

"The correct position of the bonding conductor connection, which should be at the point of entry into the building or at the first available position where the gas installation pipe becomes accessible within the building – although this may be some distance away from the gas meter. Accordingly, most engineers accept the bonding conductor termination to be within the meter cupboard."

I think that would preclude bonding in a different building?

 

[Rockingit]

Divorce the earth into the garage and make it a separate TT? Therefore, bond the gas locally.

 

[Mike Johnson]

Divorce the earth into the garage and make it a separate TT? Therefore, bond the gas locally.

Would make more sense than bonding in a different building, except that would not connect it to the MET in the Bungalow, but would to the Garage CU/MET which I suppose would be acceptable if a test confirmed continuity into the Bungalow, but that would use the gas piping as a conductor?

 

[Rockingit]

Would make more sense than bonding in a different building, except that would not connect it to the MET in the Bungalow, but would to the Garage CU/MET which I suppose would be acceptable if a test confirmed continuity into the Bungalow, but that would use the gas piping as a conductor?

Still bond it in the Bungalow as well. No difference to the usual spiders-web of bonding that happens when you've got water services (bonded) running into a gas boiler that's also bonded.

 

[7029 dave]

Divorce the earth into the garage and make it a separate TT? Therefore, bond the gas locally.

I did think about that, but the outlet pipe going to the house needs picking up, IMO you cant bond this pipe in 2 sections separately. Tin hat on

 

[Mike Johnson]

Simple solutions are always the best, bond in both buildings, we all get there in the end.

 

[telectrix]

Simple solutions are always the best, bond in both buildings, we all get there in the end.

don't you mean both ends?

 

[Timbo]

Google has the answer: