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mathew stouffer
03-30-2012, 08:46 PM
Duplex built in 1996. This appears to a ground and bonding cable. Can both be on the gas line. There was three and I have no idea where one went. Vage question but I'll ask anyway.

Robert Meier
03-30-2012, 08:57 PM
There's nothing to prohibit the connection of a bonding jumper to a metallic gas pipe. The NEC only tells us that the gas pipe cannot be used a grounding electrode.

Garry Blankenship
03-30-2012, 09:00 PM
Assuming the gas line is metalic / conductive, it must be bonded to the ground grid. However, it cannot be used as the service grounding electrode.

Robert Meier
03-30-2012, 09:16 PM
With the exception of the newer CSST flexible gas pipe it is usually bonded to the electrical system by the EGC feeding a gas appliance.


250.104(B) Other Metal Piping. Where 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 the service equipment enclosure, the grounded conductor at the service, the grounding electrode conductor where of sufficient size, or the one or more grounding electrodes used. The bonding jumper(s) shall be sized in accordance with 250.122, using the rating of the circuit that is likely to energize the piping system(s). The equipment grounding conductor for the circuit that is likely to energize the piping shall be permitted to serve as the bonding means. The points of attachment of the bonding jumper(s) shall be accessible.

mathew stouffer
03-31-2012, 03:36 AM
Thanks. Two were bonders the other Im not sure.

Rollie Meyers
03-31-2012, 06:26 AM
If it was natural gas, the serving utility would most likely have rules against grounding to the gas line, before the UG lines to my house where replaced, there was a plastic bushing to isolate the house line from the PG&E lines, seeing the copper lines, makes me think propane is the fuel in the OP's photo, & would suspect a propane supplier would have additional prohibitions besides the NEC also.

Robert Meier
03-31-2012, 06:35 AM
The gas line is already bonded to the eletrical system by the EGC in the appliance(s) it's connect to. When you plug in a gas stove to a wall receptacle the gas pipe is connected to metal frame of the stove which is grounded so adding an additional bonding jumper somewhere shouldn't really matter. Using the underground portion of the gas pipe as an eletrode is another matter and is specifically prohibited by the NEC.

Jerry Peck
03-31-2012, 07:33 AM
Presuming that it is bonding the gas line and other items to ground, then the issue would be in the more-than-one bonding conductor in a terminal designed for one conductor (at least that is the way it looks in the photos).

Those are some pretty good sized bonding conductors, hopefully they are not using the gas piping as a grounding electrode - there is no practical way for you to determine this at this time, you would need to be able to trace the grounding electrode conductor from the service down to its grounding electrode, and be able to trace each of those bonding (grounding?) conductors back to their origination point.

I do see PB water piping at that wall, both for the water service in and what looks to be distribution piping.

Doctor Haus
03-31-2012, 04:53 PM
seeing the copper lines, makes me think propane is the fuel in the OP's photo, & would suspect a propane supplier would have additional prohibitions besides the NEC also.

Black pipe to the shutoff valve, gas appliance connector thereafter. The copper pipe you see is the TPRV discharge pipe to the floor. 1996 install would have been earlier edition for Utah. At that time all metallic gas pipe, even sections, had to be physically bonded via a junper. Permissive use of the egc for a circuit proving power to the appliance if present (this Water Heater doesn't have one) for bonding was introduced in later code cycles. Dielectric isolation and insulator outside before gas meter inlet has to be there to isolate from DC current cathodic protection on utility pipeline/mains if the gas service pipe is copper.

Fabric strapping on the Water heater is inappropriate seismic restraint for a fuel fired water heater.

Need a closeup of the actual point of contact(s).