I am trying to figure out what size conductor to run for a cold water bond. I have a building with only one sink and no hot water. The water comes to the building underground in PVC with less than 10' metal piping. The metal water pipe stubs directly out of the slab to the sink location. There is no other water piping beyond this one sink. Would this even be considered a metal water piping system. Please answer with direct references to the NEC. I will have to present this to the inspectors and engineers.
cold water bond
- Thread starter andyandy
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mcclary's electrical
Senior Member
- Location
- VA
Your pipe does not meet 250.52 (A) (1) so it cannot be used as an electrode.
Second, a "metal water piping system" to me,,,would have to have more than one pipe in order to be considered a system, since a system is multiple things working together.
If this is a single pipe,,,that is not likely to become energized, then I say it needs nothing. If it evers hits a water heater, then the bond would be made by 250.122,,,the EGC. per 250.104 (b)
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- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
I tend to agree with Mcclary-- boy that's a first. :grin:
- Location
- Logan, Utah
I disagree, 250.104(B) is for other metal piping systems. Metal water piping systems must be bonded in accordance with 250.104(A).
Chris
andyandy, as demonstrated here, the answer is going to depend on what your AHJ feels is a "system". I agree with Dennis and Mac, but your inspector may side with Chris.
An unknown factor would be if the pipe is likely to become energized. As that is one of the reasons behind bonding, your AHJ will end up being the deciding individual.
An unknown factor would be if the pipe is likely to become energized. As that is one of the reasons behind bonding, your AHJ will end up being the deciding individual.
- Location
- Logan, Utah
My post was geared to pointing out that metal water pipe bonding must be done in accordance with 250.104(A) and not (B).
I don't know that I necessarily believe what the OPer has would be a "piping system" or just an isolated section of metal water piping.
mcclary's electrical
Senior Member
- Location
- VA
My post was geared to pointing out that metal water pipe bonding must be done in accordance with 250.104(A) and not (B).
I don't know that I necessarily believe what the OPer has would be a "piping system" or just an isolated section of metal water piping.
Chris,
I understand what you're saying, but I purposefully did not use (a) because I don't consider his a "water piping system"
Second Augie, I see what you're saying but if there's no electric, how can his pipe be considered "likely" to become energized. In the FPN (i know not enforcable) they descibe likely to be energized,,,,and it doesn't sound anything close to the op IMO
cripple
Senior Member
- Location
- Santa Fe, New Mexico
cold water bond
The cold water pipe, as you noted is in contact with earth and accessible, it would be my opinion it should be bonded to the system. The sizing of the bonding jumper it would be sized per 250.104(A)(1) or (3).
The cold water pipe, as you noted is in contact with earth and accessible, it would be my opinion it should be bonded to the system. The sizing of the bonding jumper it would be sized per 250.104(A)(1) or (3).
As noted, I imagine there will be various calls. Similar discussions have occurred on the metal "stubs" at water heaters and tubs.
Somewhat like the infamous 230.70 "nearest the point of entrance", the length of a section of pipe necessary before considering it as needing to be bonded will vary inspector to inspector unless the jurisdiction prescribes a minimum length.
Somewhat like the infamous 230.70 "nearest the point of entrance", the length of a section of pipe necessary before considering it as needing to be bonded will vary inspector to inspector unless the jurisdiction prescribes a minimum length.
mcclary's electrical
Senior Member
- Location
- VA
ok,,,but what if we steer away from whether or not it's a "system",,,and steer towards whether or not it is "likely" to become energized?.
Wait,,,that wording isn't clear either
I guess I don't see how 250.104(B) could apply to this. If it is a "system" then it is a water piping system, so 250.104(A) applies. If it isn't a "system", then neither (A) or (B) apply, because 250.104(B) also only applies to systems... just something other than water piping.
In this case, I think "likely to become energized" is a moot point. If it is a system, then 250.104(A) applies and that section does not contain the "likely to become energized" language. If it is a metal water piping system, it needs to be bonded whether or not it is likely to become energized.
If it is not a "system", then it does not need to be bonded whether or not it is likely to be energized, because neither 250.104(A) nor (B) apply.
throttlebody
Senior Member
- Location
- Martinsburg, WV
The water pipe would part of the delivery method that makes up part of the water system.
I would turn my cheek if 3 ft of isolated water pipe without potential of becoming energized were not bonded, as it is the same as making someone bond the metal mesh encapsulating a short section of flexible water hose leading from a valve to a toilet.
I would turn my cheek if 3 ft of isolated water pipe without potential of becoming energized were not bonded, as it is the same as making someone bond the metal mesh encapsulating a short section of flexible water hose leading from a valve to a toilet.
- Location
- Massachusetts
But that is not what the NEC says.
The NEC speaks of a 'metal water piping system'
A few feet of metal pipe in a water piping system does not make it a 'metal water piping system'.
mcclary's electrical
Senior Member
- Location
- VA
I was swinging off memory,,,after reading your post I see exactly what you mean and I agree. Although I still don't call this a system.
throttlebody
Senior Member
- Location
- Martinsburg, WV
What is the article number where the NEC gives a minimum length of metal water piping to be a system please?
2902 of the IBC will tell you, so will the IPC. Storage, warehouses, storehouses, freight depots. minimum = 1 service sink.
Example:
Plastic entering, 3ft of metal pipe, a valve, hose termination and a sink = system.
In this case, though I'd hate to do it, I would have to call it a metal water piping system. If the metal water pipe isn't a system, then the building doesn't have a water piping system. I don't think you can have running water without a piping system. This illustrates the fact that the code needs to be more specific. Maybe the reference to "system" needs to be dropped and instead specify the length of metal pipe that triggers the bonding requirement.
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