If a new construction house has plastic main water line coming in, does the copper plumbing system along with the black pipe gas system and the ductwork need to be bonded back to the service panel?
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Yes, copper water supply system and black iron gas lines need to be bonded to a ground
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I agree with Michael, the Gas & water lines should be bonded.
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They are bonded for lightening protection.
According to the NEC metal water piping systems must be bonded, isolated sections of metal water pipe do not require bonding. Black gas pipe is bonded via the EGC run with the branch circuit feeding the gas appliance(s) and no further bonding is required. CSST gas piping may have further bonding requirements based on the manufacturer.
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Thank you everyone
So in this situation would the water system be considered isolated since it has a plastic water main line?
Good question, short answer is no. If the supply is plastic but the structure has an entire water piping system it needs to be bonded. Key word here is system.
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It is only isolated in the sense that the main is not a metal electrode. Cold and hot are 2 different systems and must be bonded. Now, if you have 2 copper stubs at the water heater then those would be isolated and not be required to be bonded.
BTW Shark Bites are not rated (electrically) and the isolate sections of the water lines.
Here’s a few code sections to go along with my previous posts. As Mike stated the plastic water piping is not a grounding electrode so the requirements for grounding electrodes are not applicable.
250.104(A)(1) General.
Metal water piping system(s) installed in or attached to a building or structure shall be bonded to any of the following:
(1) Service equipment enclosure
(2) Grounded conductor at the service
(3) Grounding electrode conductor, if of sufficient size
(4)One or more grounding electrodes used, if the grounding electrode conductor or bonding jumper to the grounding electrode is of sufficient size
The bonding jumper(s) shall be installed in accordance with 250.64(A), 250.64(B), and 250.64(E). The points of attachment of the bonding jumper(s) shall be accessible. The bonding jumper(s) shall be sized in
accordance with Table 250.102(C)(1) except that it shall not be required to be larger than 3/0 copper or 250 kcmil aluminum or copper-clad aluminum and except as permitted in 250.104(A)(2) and 250.104(A)(3)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.
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I waited until today for others to answer seeing there is, what I consider, confusion.
Specifically, for Robert M. I did not want to get ahead of a expert.
Black iron gas lines are grounded/bonded by the supplier. It is the responsibility of licensed gas contractors and homeowners to ensure that a licensed electrical contractor performs this scope of regulated work. In short as long as there is no manifold and the material remains the same to the appliance, no bonding required… The NG piping has been bonded by the supplier.
Mike Holt’s Forum-Moderator: “There is no requirement to bond the water in the building water system. There also is no requirement to bond isolated section(s) of metal water pipe either as they do not fall under a metal piping system.”
Bonding HVAC ductwork. There is not a requirement to bond the metal ducts , but the Informational Note following 250.104(B)Bonding other metal piping.
(1) Other metal piping. If installed in or attached to a building or structure, a metal piping system, including gas piping, capable of becoming energized shall be bonded to any of the following:
(a) Equipment grounding conductor for the circuit that is likely to energize the piping system.
(b) Service equipment enclosure.
(c) Grounded conductor at the service.
(d) Grounding electrode conductor, if of sufficient size.
(e) 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 or conductors, or the jumper or jumpers 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 or systems. The points of attachment of the bonding jumper or jumpers shall be accessible.
I think the confusion lies on, How far should you keep wires away from plumbing pipes or ductwork?What distance should be kept between electrical wires or boxes and nearby plumbing pipes or HVAC ducts? Some basic wire clearance distances are given in Carson Dunlop Associates’ sketch below, used with permission.
https://inspectapedia.com/electric/Electrical-Wire-Clearances.php
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If the water supply from the utility is poly (plastic) then bonding to the distribution copper is not required. Also bonding is not required to the gas lines unless certain CSST is in use. (Home-Flex) is one that requires bonding.
If there is an interior metal water piping system that is fed with a plastic supply pipe it is still required to be bonded. See the applicable NEC section in post #10.
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Thank you as always. I feel the confusion on my part steams from the verbiage lay with the question, does the copper/metal plumbing system need to be bonded back to the service panel? Service panel being the moniker.
It will be directly or indirectly connected to the service. Take look at the methods in post #10. An example of a direct connection will be by bonding it to the service neutral. An indirect connection would be via the GEC.
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I concur. Bonding can be archived via various methods. Many fall under limitations due to not visually accessible.
That’s correct and it differs from the connection to a metal piping system where the incoming pipe qualifies as an electrode. In that case the connection must be within 5’ of the entry of the pipe into the structure. For simply bonding the metal piping system the connection to the pipe can be at any accessible location.
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I agree, Robert. I had been called to a house with plumbing leks in the copper plumbing. Multiple pinholes in pipes. The meter box was grounded to the copper plumbing, however, at some point in time the well pump and adjacent plumbing in the garage had been replaced using PVC pipe, requiring all grounding to go through the water IN the pipes to get to ground. This required electrolysis to eat copper from the inside of the pipes to carry the current to ground resulting in all the copper plumbing to become paper thin and in need of full replacement.
So, there’s that.
I’ve heard about this but from what you’ve described under normal conditions there would be no current flowing on the pipes or in the water so I’m not sure how it relates to the pin holes.
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Bonding is required. It just may not require the ‘new’ methods added because of CSST.
Bonding is usually present via the appliance circuit however, this bond may be missing if the HVAC contractor does not add a EGC when changing out a furnace wired in 2-wire. Use to see it all the time.