Bonding gas pipes

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sfav8r

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Here in San Francisco we are required to bond the gas pipe withing 5' of where it enters the premises. We just did a job in another jurisdiction and bonded the gas pipes as we always do. The inspector called us on the installation stating that the gas pipe must be bonded at the hot water heaters. 210.104(B) states that the gas pipes must be bonded to "service equipment enclosure, the grounded conductor at the service, the grounding electrode conductor where of sufficient size, or to one or more of the grounding electrodes." How does bonding the gas pipe at the hot water heater meet this requirement? Even if it did meet the requirement, where in the code does it say we can't bond it the way we did? Also, he is requiring us to remove the hot/cold bond because we used #6 stranded and he says it has to be solid. I thought that requirement only applied to hot tub bonding. It's not a big deal to correct this, I just resent having to make correction that I don't believe are necessary. You'd think I'd be in a better mood after last nights Giants game!
 
Normally when there is gas at a house one needs not go any further then wiring , say, the gas furnace. The egc of that circuit will suffice, however there is nothing saying that you cannot bond to withn 5' of the gas pipe entering the building with 250.66 if you want to.
 
Dennis Alwon said:
Normally when there is gas at a house one needs not go any further then wiring , say, the gas furnace. The egc of that circuit will suffice, however there is nothing saying that you cannot bond to withn 5' of the gas pipe entering the building with 250.66 if you want to.
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I'm thinking that EGC for the furnace would only be #12. The bonding whould be #8 for the piping system so it doesn't seem like that owuld fly for meeting 250.104(B). 250.66 also requires #8.
 
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I agree with Dennis. The problem with bonding other metal piping is the question of rather it's likely to become energized. Yet, to bond all metal piping doesn't hurt---seeing that it may provide additional safety.

We always hit the gas pipe at the furnace. In most cases jumping from the piping serving the H20--using T. 250.66
 
You might ask if its a "local requirement"...
Some of the inspectors in this area have "requested" that the hot-cold-gas bond be completed at the water heater as a courtesy and conformity to make it easy to locate. It has not made it to the "required" status just a often recognized agreement.
 
sfav8r said:
I'm thinking that EGC for the furnace would only be #12. The bonding whould be #8 for the piping system so it doesn't seem like that owuld fly for meeting 250.104(B). 250.66 also requires #8.
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The #12 is code compliant. It does not state the egc for the circuit that is likely to energize the circuit needs to be #8.

250.122 is for egc -- 250.66 is for other bonding however 250.104(B) clearly states that 250.122 can be used to bond the gas pipe
 
How does a jumper from the hot to cold to gas at the hot water heater meet 250.104(B)? The hot and cold water pipes at the hot water heater are not "the service equipment enclosure", "the grounded conductor at the service", "the grounding electrode conductor", or a "grounding electrode." The only part of the water pipe that is considered part of the grounding system is within 5' of where it enters the building.
 
Dennis Alwon said:
The #12 is code compliant. It does not state the egc for the circuit that is likely to energize the circuit needs to be #8.

250.122 is for egc -- 250.66 is for other bonding however 250.104(B) clearly states that 250.122 can be used to bond the gas pipe
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...it also says: The equipment grounding conductor for the circuit that is likely to energize the piping shall be permitted to serve as the bonding means.

However, the requirement is bonding the piping. While the egc will likely ground the piping through the furnace's metallic parts, I believe a wire-type bonding jumper from the egc to the piping itself would be the strict interpretation.
 
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sfav8r said:
How does a jumper from the hot to cold to gas at the hot water heater meet 250.104(B)? The hot and cold water pipes at the hot water heater are not "the service equipment enclosure", "the grounded conductor at the service", "the grounding electrode conductor", or a "grounding electrode." The only part of the water pipe that is considered part of the grounding system is within 5' of where it enters the building.
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That is the problem, when you take the code down to "What it actually says" you don't need to do several things that are commonly required by inspectors. When you look at a house with all metal water piping there are many places that the hot and cold lines are connected, shower valves, faucets, copper mounting brackets,etc. you shouldn't even need to jumper the hot and cold. Then you only need bond the gas line at "the circuit likely to energize it" AKA the branch circuit feeding the gas appliance, if cord and plug connected the receptacle ground does the job. So you really should only need to bond to the main water service "if metal".
 
Just as there are many ways to skin the cat, there are many ways to assure the bonding of piping systems. Are the water heater tanks metallic ? how about the plumbing fixtures ? Is there an electric supply to the gas appliance ?
Answering these and other associated questions can require some visual checks and often documentation.
Who has the responsibility to document and assure these methods are
in place and sufficient ? The inspector ? The Contractor ?
Is this a situation where you want to delay the approval of the job awaiting the documentation or the inspectors return to locate the bonding method with which he was not aware ?
In this area it was determined for simplification and consistency, the E/C would bond the gas/cold and hot at the water heater to assure there was the required bond path and to provide a consistent location to inspect it.
Is it a requirement ? No. Does it simplify the inspection expediting the Final Approval ? Yes It is worth it for you to do that ? Judgment call.
 
It's like the second ground rod issue, it's easier and cheaper to just do it then to get turned down on an inspection.
 
Why does SF require bonding gas pipe within 5 feet of entering building? It likely has a dielectric fitting on the gas meter with part of the intention of that being the gas line will not become an electrode for the electrical system.

All new gas service laterals around here are using a nonmetallic pipe undergound and only a steel pipe as a riser out of the ground.
 
Will someone enlighten me to why a #4 CU wire is required to bond the water pipes in a house where there are no other primary electrodes. It seems like over kill to me. Service is 4/0 AL. City water is fed by a ploy pipe. Nothing in the footings either. Table 250.66 reqires #4 Cu. I can see that because you are trying to stabilize your potential to ground. But bonding the interior water pipes to the service #4 CU just seems a bit over kill.
 
FrancisDoody said:
Will someone enlighten me to why a #4 CU wire is required to bond the water pipes in a house where there are no other primary electrodes. It seems like over kill to me. Service is 4/0 AL. City water is fed by a ploy pipe. Nothing in the footings either. Table 250.66 reqires #4 Cu. I can see that because you are trying to stabilize your potential to ground. But bonding the interior water pipes to the service #4 CU just seems a bit over kill.
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If there is no outside metal piping on the water service (if it is all PVC underground) you don't need to run a wire to the main, you just need to bond the interior piping (if it is metal and not PEX)
 
acrwc10 said:
If there is no outside metal piping on the water service (if it is all PVC underground) you don't need to run a wire to the main, you just need to bond the interior piping (if it is metal and not PEX)
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I think he is asking "Why do I have to still use #4 for bonding the pipes, if I am not using the pipes as a grounding electrode? What is the physics/reasoning behind it? Isn't a smaller wire smaller sufficient?"

He thinks it is overkill in his words.
 
jumper said:
I think he is asking "Why do I have to still use #4 for bonding the pipes, if I am not using the pipes as a grounding electrode? What is the physics/reasoning behind it? Isn't a smaller wire smaller sufficient?"

He thinks it is overkill in his words.
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That is a tough one. Your brain might explode tring to figure out "WHY".:grin:
 
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acrwc10 said:
It's like the second ground rod issue, it's easier and cheaper to just do it then to get turned down on an inspection.
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I have not finished reading the thread, but this type of response is enough to make me jump off a 7" step. ;)

Carry a code book, be familar with the areas of the NEC that you do most of your work, and be prepared to let the inspector that you respect his opinion, but the code says xxx, in Section xxx.xx.
 
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