Water heater bonding in NJ

S

SceneryDriver

Senior Member
Location
NJ
Occupation
Electrical and Automation Designer
Here in NJ, almost every water heater has the bonding jumper right above the water heater, bonding the cold water and hot water plumbing together. Makes sense when the entire plumbing system is copper / otherwise metallic.

I was recently told that even in a plumbing system with primarily PEX, it's "required" to have 18" of copper out the top of the water heater to attach the bond to, even if it's PEX to and from the water heater. That's about the dumbest thing I've heard in a while.

I was told by a plumber that, "It's so the house will pass the home inspection on resale. Home inspectors are taught to look for the jumper." Is this actual code in NJ, or is the plumber uninformed. I certainly wouldn't care at all what a home inspector has to say.


SceneryDriver
 
No it's not required to bond an 18" length of copper pipe so installing it for that purpose is incorrect. If the entire water piping system is metal than a bonding jumper across the hot and cold water pipes is required here in NJ. Home inspections often call out things that are not required by code.
 
Dennis Alwon said:
I think @infinity would agree, there is no telling what an inspector may call you on but it isn't in the code and not a NJ amendment
Click to expand...
I never heard of this and agree that it's more likely an electrical myth propagated by someone who doesn't understand anything about bonding. Also it's funny that a bonding jumper between the hot and cold water pipes isn't explicitly mentioned in the NEC. Some say it's not required other say that it is like here in NJ. I wrote a proposal years ago to clarify that the jumper is not required but it was rejected.

Public Input No. 4314-NFPA 70-2014 [ Section No. 250.104(A)(1) ]
(1) General.
Metal water piping system(s) installed in or attached to a building or structure shall be bonded to the service equipment enclosure, the grounded conductor at the service, the grounding electrode conductor where of sufficient size, or to the one or more grounding electrodes used. The bonding jumper(s) shall be sized in accordance with Table 250.66 except as permitted in 250.104(A)(2) and (A)(3). Bonding jumpers shall
not be required between the hot and cold water piping systems at hot water heaters to maintain the continuity of the piping system.
Statement of Problem and Substantiation for Public Input
Substantiation: There seems to be some confusion as to when applying 250.104(A)(1) that a hot water heater requires that the continuity between the hot and cold piping be maintained by the use of a bonding jumper, similar to the ones required by 250.68(B) around water meters, etc. Sections 250.104(A)(1) and 250.68(B) are different in that bonding jumpers required by 250.68(B) are to maintain the continuity of grounding electrode, the same continuity requirement does not apply to the bonding of piping systems. This additional wording will clarify that bonding jumpers are not required around hot water heaters to comply with 250.104(A)(1).
Submitter Information Verification
Submitter Full Name: robert meier
Organization:
NA
Street Address:
City:
State:
Zip:
Submittal Date:
Thu Nov 06 19:02:22 EST 2014
Committee Statement
Resolution: Plumbing fittings and fixtures may not always provide reliable bonding between hot and cold waterlines.
Click to expand...
 
infinity said:
No it's not required to bond an 18" length of copper pipe so installing it for that purpose is incorrect. If the entire water piping system is metal than a bonding jumper across the hot and cold water pipes is required here in NJ. Home inspections often call out things that are not required by code.
Click to expand...
That's what I thought, and what makes sense. Not sure what bonding two short sections of copper would accomplish if the supply is PEX. The re-pipe will primarily be PEX, with some short sections of copper where it makes sense, and where it ties into existing plumbing that isn't being changed.

I've seen local requirements and even a few mfg instructions that call for copper stubs at the water heater, but that was on gas-fired units where the PEX could get too close to the flue pipe. This is a heat pump water heater.


SceneryDriver
 
SceneryDriver said:
I've seen local requirements and even a few mfg instructions that call for copper stubs at the water heater, but that was on gas-fired units where the PEX could get too close to the flue pipe
Click to expand...
Copper stubs may be required for other purposes but they are not required for bonding.
 
I've been inspecting fulltime for two years and have never required bonding at a water heater when the home is plumbed with PEX.

Unfortunately, things get out there and many just go with it.

On another note, here's and older Construction Code Communicator article about bonding of water heaters. Note, CCC articles are not formal NJ interpretations.

Water Heaters and Bonding

Bonding jumpers are required for water heaters in accordance with the 2002 edition of the National Electrical Code, Section 250.104, entitled “Bonding of Piping Systems and Exposed Structural Steel.” Section 250.104(B), “Other Metal Piping,” states that “metal piping systems that may 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 to the one or more grounding electrodes used.” The bonding jumper shall be sized in accordance with Section 250.122, “Size of Equipment Grounding Conductors,” using the rating of the circuit that may energize the piping system. The equipment grounding conductor for the circuit is to be allowed to serve as the bonding means. The points of attachment of the bonding jumper must be accessible. If, at the time of replacement, an existing water heater has no bonding jumper but has an equipment grounding conductor present, then no bonding jumper would be required to be installed because the equipment grounding conductor is allowed to serve as the bonding means. However, if there is no bonding jumper or equipment grounding conductor present at the time of replacement, particularly with gas water heaters, then a bonding jumper must be installed and an electrical permit is required.

If you have any questions on this matter, you may reach me at (609) 984-7609.
Source: Suzanne Borek Code Assistance Unit
 
HIGuy said:
It’s likely done with copper to maintain a proper clearance of combustibles to a single wall flue for a gas fired water heater.
Click to expand...
As a home inspector would you call out the short sections of metal pipe to be bonded?
 
Ken_S said:
I've been inspecting fulltime for two years and have never required bonding at a water heater when the home is plumbed with PEX.

Unfortunately, things get out there and many just go with it.

On another note, here's and older Construction Code Communicator article about bonding of water heaters. Note, CCC articles are not formal NJ interpretations.

Water Heaters and Bonding

Bonding jumpers are required for water heaters in accordance with the 2002 edition of the National Electrical Code, Section 250.104, entitled “Bonding of Piping Systems and Exposed Structural Steel.” Section 250.104(B), “Other Metal Piping,” states that “metal piping systems that may 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 to the one or more grounding electrodes used.” The bonding jumper shall be sized in accordance with Section 250.122, “Size of Equipment Grounding Conductors,” using the rating of the circuit that may energize the piping system. The equipment grounding conductor for the circuit is to be allowed to serve as the bonding means. The points of attachment of the bonding jumper must be accessible....
Click to expand...
There are a couple of issues here as mentioned
250.104(A) requires any metallic water piping systems installed in or attached to a building must be bonded to the Grounding Electrode System.

A) The bonding wire to water pipes is sized per T250.102(C) not T250.122

B) A piping system is usually defined an assembly of interconnected pipes, fittings, flanges, valves, and other components that transport fluid from a source to its destination. The destination would be a plumbing fixture.

C) There is no 'likely to become energized' exception for a water piping system.

If its a short stub of copper that transition to PEX thats of course not a metal piping system.
However if the plumber has a run of copper between a water heater and a water meter or a expansion tank or other plumbing fixture that could be interpreted as a metallic piping system.

250.104(B) requires metallic gas pipe to be bonded, CSST has specific bonding instructions that do not allow the appliance to be the sole bonding connection. Also those flexible gas appliance whips cannot serve a bonding conductor.
 
WD40 said:
However if the plumber has a run of copper between a water heater and a water meter or a expansion tank or other plumbing fixture that could be interpreted as a metallic piping system.
Click to expand...
Interesting thought but IMO that short section of metal pipe is in no way a system.
 
infinity said:
Interesting thought but IMO that short section of metal pipe is in no way a system.
Click to expand...
When I ran into the issue the plumber had way more than a 18" stub, he ran a copper line across a basement from the water meter to a filter, then water heater then an expansion tank. The rest was pex going upstairs. I am not sure why he did not use pex for everything.
I tried arguing that the metallic water pipe is not likely to become energized (gas water heater), but that only applies to other piping. Here if you go between two plumbing devices you have a system, a 18" stub no way.
It does seem excessive to size it to T250.102(C).
 
You must log in or register to reply here.
Top