Gas piping in residential wiring.

[Electric Doug]

An inspector recently failed a house we finished because the ridgid metal natural gas pipes were not grounded, and gave the code referance of 250.6. Objectionable Current over Grounding Conductors. Can anyone enlighten my intellect a little. And is there a good electrical dictionary I should get to explain some of the terminolgy in the NEC besides the hand book.

 

[Dennis Alwon]

An inspector recently failed a house we finished because the ridgid metal natural gas pipes were not grounded, and gave the code referance of 250.6. Objectionable Current over Grounding Conductors. Can anyone enlighten my intellect a little. And is there a good electrical dictionary I should get to explain some of the terminolgy in the NEC besides the hand book.

Read this thread
http://forums.mikeholt.com/showthread.php?t=82829

 

[romeo]

Gas piping in residential wiring.

Read this thread
http://forums.mikeholt.com/showthread.php?t=82829

The gas piping is required to be bonded. I think the NEC section he should be using is 250.104(3)(B)

 

[bphgravity]

Yes, 250.104(B) would be the correct reference. 250.6 does not apply for the installation described.

 

[mvannevel]

250.104(B) requires metal gas piping to be bonded, but it allows the equipment grounding conductor for the circuit that may energize the piping to serve as the bonding means.

 

[George Stolz]

...gave the code referance of 250.6. Objectionable Current over Grounding Conductors.

250.6 is generally interpreted to be mainly dealing with neutral current flowing on EGCs and GECs.

 

[infinity]

250.104(B) requires metal gas piping to be bonded, but it allows the equipment grounding conductor for the circuit that may energize the piping to serve as the bonding means.

This has always been he accepted practice here. The EGC supplying the gas appliance(s) effectively bonds the gas pipe.

 

[mvannevel]

This has always been he accepted practice here. The EGC supplying the gas appliance(s) effectively bonds the gas pipe.

Same here, but it was nice when they included that language for gas piping in the '02 cycle. I still see a lot of contractors that will run a full size bonding conductor to the gas piping though.

The wording of 250-104(b) for bonding the gas piping in the '99 Code was extracted from the Fuel Gas Code. My understanding is that it was the intent of the Fuel Gas Code that the circuit supplying a gas appliance was suitable for this bonding, but it wasn't written that way in the '99 Code. Somewhere around the office I have a Formal Interpretation from NFPA to that effect. They fixed the wording in '02 and everybody could relax. That is until Gastite issued their tech bulletin for CSST...

 

[james wuebker]

The only problem that could come up is if the pipe had a die-electric type fitting on it then you would have to put a jumper on it.

Jim

 

[raider1]

This has always been he accepted practice here. The EGC supplying the gas appliance(s) effectively bonds the gas pipe.

That has always been my pratice as well.

The only problem that could come up is if the pipe had a die-electric type fitting on it then you would have to put a jumper on it.

Yes, but the jumper would only have to be sized to match the EGC of the circuit that feeds the gas appliance.

Chris

 

[james wuebker]

That has always been my pratice as well.



Yes, but the jumper would only have to be sized to match the EGC of the circuit that feeds the gas appliance.

Chris

Yes, you are correct Chris.

Jim

 

[iwire]

The only problem that could come up is if the pipe had a die-electric type fitting on it then you would have to put a jumper on it.

Jim

If there is a die-electric fitting why would the gas line still be likely to be energized?


In my opinion 250.104(B) does not require a gas line that is not electrically connected to an electric appliance to be bonded.

250.104(B) only requires we bond 'other metal piping' if it 'may' become energized.

If the pipes are not connected to electric equipment it is unlikely they will become energized.

If they are we will also have to start bonding metal waste pipes and down spouts.