Was doing a new construction inspection today and it just so happened that the city electrical inspector and I wound up at the panels at the same time. We were comparing notes on deficiencies and I mentioned that I had not yet seen a bonding connection to the gas piping. He had not either. I told him I’d take a look for it when I was in the mechanical room in case it was there and we each proceeded with our individual inspections.
He came and tracked me down later to tell me that according to his office, they have been permitting the electrical contractors to rely on the egc at the furnace as the bonding means. I pulled the make-up cover off the furnace so we could make sure that the unit was grounded and discussed it a bit further. The egc inside the furnace was only 14AWG and it was on the appliance side of the gas appliance connector. It just didn’t seem right to rely on this as the bonding means. He said he would follow up as did I.
Well the AHJ tracked me down a little later and handed me a sheet of paper and said the reference was in NEC article 250-104 (this was a good city inspector to work with).
So back at the office, I peruse the article and find this under subsection B
Interested in thoughts on this alternative bonding means from our resident master electricians. There was no separate jumper from the egc in the furnace cabinet for the metal gas piping so the control valve and the flexible appliance connector with be part of the bonding path. It just doesn’t “feel right” to me. Is a separate jumper required from the metal gas pipe to the egc when doing it this way?