Bonding at water heater

[deckscrew]

I'm a GC in the SF Bay Area. We recently completed a kitchen remodel and on the final inspection the building inspector is making us run a bonding wire from the gas line to the hot and cold water lines at the water heater and bring to a nearby subpanel. These are located in the garage near each so its not hard to do. My electrician says it isn't necessary or correct, he says just run it from the cold water to the gas line. My dilemma is I've got to deal with this inspector on other jobs, so I don't really want to go to the mat on this issue so I'll do what he asks. My question is, is this a hazard or is it just a a pointless, yet harmless exercise?

 

[LarryFine]

It can be harmful if there is any CSST between the bonding point and the incoming gas service.

 

[deckscrew]

It can be harmful if there is any CSST between the bonding point and the incoming gas service.

No CSST, all steel pipe. This is an older house.

 

[infinity]

No CSST, all steel pipe. This is an older house.

If it's black gas pipe the NEC does not require any external bonding. Unless there is a local amendment to the NEC it is not required to bond the gas pipe at all with anything other than the equipment grounding conductor installed with the branch circuit to a gas appliance.

 

[Dennis Alwon]

As stated, if you have a has furnace then the bonding is not necessary unless there is csst in the house. The inspector may be thinking that the flex line to the range is csst but he would be incorrect.

250.104(B) Other Metal Piping. If installed in or attached to a building
or structure, a metal piping system(s), including gas piping,
that is likely to become energized shall be bonded to any of the
following:
(1) Equipment grounding conductor for the circuit that is
likely to energize the piping system
(2) Service equipment enclosure
(3) Grounded conductor at the service
(4) Grounding electrode conductor, if of sufficient size
(5) One or more grounding electrodes used, if the grounding
electrode conductor or bonding jumper to the
grounding electrode is of sufficient size
The bonding conductor(s) or jumper(s) shall be sized in
accordance with Table 250.122, and equipment grounding
conductors shall be sized in accordance with Table 250.122
using the rating of the circuit that is likely to energize the
piping system(s). The points of attachment of the bonding
jumper(s) shall be accessible.

 

[electrofelon]

I have never been able to convince an inspector that bonding the gas pipe is not necessary. Seems that there logic is that it is not just the circuit feeding the appliance that is likely to energize the gas piping, it could be any other circuit that comes near or in contact with the piping. BS but hard to counter if they get to decide what "likely" means

 

[LarryFine]

That's because they see it like water piping.

 

[infinity]

I have never been able to convince an inspector that bonding the gas pipe is not necessary. Seems that there logic is that it is not just the circuit feeding the appliance that is likely to energize the gas piping, it could be any other circuit that comes near or in contact with the piping. BS but hard to counter if they get to decide what "likely" means

If you go by the strict definition of the word "likely" then it is likely that it will almost never become energized.

 

[Ponchik]

If you have your service bonded at the water pipe then all you need is bonding from cold, hot, gas at the water heater. What does it have to do with a sub panel.

My dilemma is I've got to deal with this inspector on other jobs, so I don't really want to go to the mat on this issue so I'll do what he asks.

I have an issue with this. Just because he is the inspector I don't follow his orders, unless it is a violation and he has a NEC or local code reference.

What city is this in?

 

[curt swartz]

If you have your service bonded at the water pipe then all you need is bonding from cold, hot, gas at the water heater. What does it have to do with a sub panel.



I have an issue with this. Just because he is the inspector I don't follow his orders, unless it is a violation and he has a NEC or local code reference.

What city is this in?

There is no NEC requirement to even do that. Hot and cold are bonded by mixer valves. Gas is bonded by the EGC of any appliance that is connected to the gas that also has an electrical connection.

 

[infinity]

There is no NEC requirement to even do that. Hot and cold are bonded by mixer valves. Gas is bonded by the EGC of any appliance that is connected to the gas that also has an electrical connection.

I agree, but here in NJ the bonding jumper at the HWH is required. I wrote a PI to have it clarified in the NEC that the bonding jumper was not required but it was rejected.

 

[Ponchik]

There is no NEC requirement to even do that. Hot and cold are bonded by mixer valves. Gas is bonded by the EGC of any appliance that is connected to the gas that also has an electrical connection.

I agree. However, some of the bay area cities do require it and since the OP is from our neck of the woods that is why I mentioned it.

 

[Lioneye]

WA state. WAC code amends the NEC to require min #6 cu bond to metallic gas piping systems. Too many components between the EGC and the metal piping system (solenoids, valves, etc) to insure a low impedance path to OCPD protection. Water pipe systems bonded per NEC. If mixing valves connecting hot and cold can be verified then H&C need not be bonded together.
it is correct to bond all these systems in case of a fault of any of them. Commercial or residential.

 

[Doc13067]

There is no NEC requirement to even do that. Hot and cold are bonded by mixer valves. Gas is bonded by the EGC of any appliance that is connected to the gas that also has an electrical connection.

I just realized the gas pipes are bonded via appliance EGC. I initially liked the idea of bonding the gas and hot water so they’re all at the same potential but what you say makes sense. But if there were no appliances then wouldn’t it be beneficial to bond the gas pipes? (Not talking about CSST)

 

[LarryFine]

But if there were no appliances then wouldn’t it be beneficial to bond the gas pipes? (Not talking about CSST)

What would be likely to energize it?

 

[Doc13067]

What would be likely to energize it?

A nearby lightning strike. Voltage traveling through the earth from the nearby lightning strike. Not that that would be likely, but possible. Reason enough for bonding.

 

[rc/retired]

But if there were no appliances then wouldn’t it be beneficial to bond the gas pipes? (Not talking about CSST)

If there were no appliances, would there be a need for gas pipe to bond?

 

[LarryFine]

A nearby lightning strike. Voltage traveling through the earth from the nearby lightning strike. Not that that would be likely, but possible. Reason enough for bonding.

That's why CSST triggers the bonding need.

 

[Doc13067]

If there were no appliances, would there be a need for gas pipe to bond?

I would think so. If there is a difference of potential and voltage travels through gas and water lines it could damage both causing gas and water leaks. But this is a good question. I don’t see what stops voltage from a nearby lightning event from traveling through gas lines if they’re not bonded to water independent of appliances (for that rare case where there are no appliances) but there may be a bond I’m not aware of or maybe we’ll see this in a future code!

 

[jaggedben]

Everybody has ignored the part of the OP where it talked about bonding pipes to a nearby subpanel. That part is wrong. Just bond the pipes to each other, not to the subpanel.

As far as what the rest of ya'll are debating, recall that the code requires bonding gas and water piping systems. Doing so at the water heater (where all the typical pipes are usually present) is seen by most inspectors I've dealt with as an easy way to do this, although it's not the only way. If you want to argue that gas is bonded at appliances, well, I'd say the onus would be on you to prove it in any given case.