Bonding the Hot Water pipe.

[pete m.]

What would justify bonding two pieces or metal pipes together?

If the metal pipes in question are part of a metal water piping system (and I am not referring to 6" pieces of metal pipe:roll how do you not and comply with the NEC?

The verbiage of the ICC Plumbing Code calls the potable water one system also. Are you saying that the inspector should require the electrician to ensure continuity of the metal piping system? AT what lengths should the inspector stop requiring the electrician to bond? At what length does a piece of pipe become a system? Which code section requires continuity?

There is no specific length of metal water piping mentioned in the NEC that automatically qualifies said piping as a "system". That being said, I have yet to witness an installation where the plumber has willy-nilly decided to switch back and forth between plastic and metal to build the "system". This could very well happen but it would be out of the ordinary in this neck of the woods.

Got a water heater in the cabinet under the sink with a short piece of copper before the supply line to the sink. Does this hot water system need to be bonded?

IMHO, a nipple, as you have described, does not constitute a metal piping system and no bonding would be required.

How about a water heater that supplies all the requisite fixtures in a home with hot water and the piping is all metallic AND happens to be electrically isolated from the metallic cold water piping, where the electrical bond is made, are you saying that the NEC does not require the hot water piping to be bonded in this example?

Pete

 

[jwelectric]

If the metal pipes in question are part of a metal water piping system (and I am not referring to 6" pieces of metal pipe ) how do you not and comply with the NEC?

The only requirement I can find only requires that the point of bond be accessible

There is no specific length of metal water piping mentioned in the NEC that automatically qualifies said piping as a "system". That being said, I have yet to witness an installation where the plumber has willy-nilly decided to switch back and forth between plastic and metal to build the "system". This could very well happen but it would be out of the ordinary in this neck of the woods.

A plumber installing nonmetallic pipes to metallic pipes is done every day especially in remodel work.

IMHO, a nipple, as you have described, does not constitute a metal piping system and no bonding would be required.

so how long does the pipe have to be to become large enough to require a bond?

How about a water heater that supplies all the requisite fixtures in a home with hot water and the piping is all metallic AND happens to be electrically isolated from the metallic cold water piping, where the electrical bond is made, are you saying that the NEC does not require the hot water piping to be bonded in this example? Pete

How would the so called hot water system be different where the water heater only has a hot water pipe that is 10 feet or less in length than one that has more than 10 feet? Does the distance the hot water has to travel make any difference in making it a system?
Do you know of section that requires the metal water pipes of a building to be electrically continuous?

 

[roger]

Mike, I haven't been keeping up with this thread but, why don't you just tell everyone how long you think a metallic pipe needs to be to be considered a system, or at least tell them how long you think it should be before it needs to be bonded.

Roger

 

[kwired]

I've seen barns where the entire water piping system for the barn is one frost free hydrant supplied by non metallic water piping. Less than 10 feet of metal pipe in the ground, and only 3-4 feet of metallic pipe exposed ending in a hose bibb. Does this piping system need bonded? Have never bonded one of these or seen it done by others.

 

[John120/240]

Bonding the hot water pipe

Bonding the hot water pipe

It is my understanding that the reason we bond hot to cold is to keep everything

at the same potential. You wouldn't want to brush your teeth, barefoot in the
bathroom & come into contact with a electrically live faucet handle.

Just my .02 cents

 

[kwired]

It is my understanding that the reason we bond hot to cold is to keep everything

at the same potential. You wouldn't want to brush your teeth, barefoot in the
bathroom & come into contact with a electrically live faucet handle.

Just my .02 cents

Only a problem on a grounded conductive floor - like concrete on earth. Still a good idea to have bonded piping though - but then a bad service neutral may cause there to be voltage from the water piping to the concrete floor.

Using system grounded conductor for current carrying is one of the dumbest things we do, there would be less hazards and misunderstandings if we did not do this.

 

[Dennis Alwon]

Mike, I haven't been keeping up with this thread but, why don't you just tell everyone how long you think a metallic pipe needs to be to be considered a system, or at least tell them how long you think it should be before it needs to be bonded.

Roger

Here was Mike's response earlier

Unless the metal water piping system is a ?complete? (100 percent) metal then there is no bonding required by 250.104(A) but instead the bonding requirements of 250.104(B) is what is required.

 

[roger]

Here was Mike's response earlier

As I said, I haven't been keeping up with the thread but, after reading further it appears as though Ron needs to be a little more consistant with what he is telling people.

Roger

 

[jwelectric]

Mike, I haven't been keeping up with this thread but, why don't you just tell everyone how long you think a metallic pipe needs to be to be considered a system, or at least tell them how long you think it should be before it needs to be bonded.

Roger

This is a good idea, thanks Roger,

5-235 Log #1834 NEC-P05 Final Action: Reject
(250.104(A)(1))
____________________________________________________________
Submitter: Mark T. Rochon, Mark J. Rochon Master Electrician
Recommendation: Revise as follows:
General Combination metal water piping system(s) separated by nonmetallic water piping system(s) where may become energized 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 the one or more grounding electrodes used.
Substantiation: Nonmetallic water piping systems are being inserted between our metal water piping system and today?s code is not recognizing these changes.
Panel Meeting Action: Reject
Panel Statement: The conditions indicated in the substantiation are already covered by 250.104(B) where there is not a complete metallic water piping system.
Number Eligible to Vote: 15
Ballot Results: Affirmative: 15
____________________________________________________________
5-236 Log #2432 NEC-P05 Final Action: Reject
(250.104(A)(1))
____________________________________________________________
Submitter: Robert P. McGann, City of Cambridge
Recommendation: Revise text to read as follows:
Metal water piping system(s) that is likely to be energized installed in or attached to a building or structure shall be bonded.
Substantiation: With much expanded use of plastic water piping system(s) isolating section of metal piping systems. This type of installation leaves contractors and inspectors what is required to be bonded.
Panel Meeting Action: Reject
Panel Statement: The requirements of 250.104(A) apply to complete metallic water piping systems. Where there is no complete metallic water piping system, then the requirements of 250.104(B) would apply for those portions of isolated metal water piping system likely to become energized.
Number Eligible to Vote: 15
Ballot Results: Affirmative: 15

I would think that the panel was saying that if there isn?t continuity then it must not be a complete metallic system.

If it was a complete system then it would already have continuity and there would be no need for a jumper. The use of a jumper in itself says that the system is not a complete metallic system and needs this jumper to maintain continuity.

 

[pete m.]

This is a good idea, thanks Roger,

5-235 Log #1834 NEC-P05 Final Action: Reject
(250.104(A)(1))
____________________________________________________________
Submitter: Mark T. Rochon, Mark J. Rochon Master Electrician
Recommendation: Revise as follows:
General Combination metal water piping system(s) separated by nonmetallic water piping system(s) where may become energized 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 the one or more grounding electrodes used.
Substantiation: Nonmetallic water piping systems are being inserted between our metal water piping system and today?s code is not recognizing these changes.
Panel Meeting Action: Reject
Panel Statement: The conditions indicated in the substantiation are already covered by 250.104(B) where there is not a complete metallic water piping system.
Number Eligible to Vote: 15
Ballot Results: Affirmative: 15
____________________________________________________________
5-236 Log #2432 NEC-P05 Final Action: Reject
(250.104(A)(1))
____________________________________________________________
Submitter: Robert P. McGann, City of Cambridge
Recommendation: Revise text to read as follows:
Metal water piping system(s) that is likely to be energized installed in or attached to a building or structure shall be bonded.
Substantiation: With much expanded use of plastic water piping system(s) isolating section of metal piping systems. This type of installation leaves contractors and inspectors what is required to be bonded.
Panel Meeting Action: Reject
Panel Statement: The requirements of 250.104(A) apply to complete metallic water piping systems. Where there is no complete metallic water piping system, then the requirements of 250.104(B) would apply for those portions of isolated metal water piping system likely to become energized.
Number Eligible to Vote: 15
Ballot Results: Affirmative: 15

I would think that the panel was saying that if there isn?t continuity then it must not be a complete metallic system.

If it was a complete system then it would already have continuity and there would be no need for a jumper. The use of a jumper in itself says that the system is not a complete metallic system and needs this jumper to maintain continuity.

Thank you for posting those Mike.

What doesn't make sense to me, and it's probably as plain as the nose on my face, is why IF we have a metallic water piping system as contemplated in 250.104(A) it matters not whether the piping is "likely to become energized".

If we have an incomplete (separated by a piece of plastic) metal water piping system 250.104(B) is only concerned with the bonding of the metal portion that is "likely to become energized".

Why the distinction?

Pete

 

[Dennis Alwon]

I still do not see how 250.104(B) pertains to partial metal piping. It still states a metal piping system. What am I missing? I see that the cmp states 250.104(B) is for incomplete metallic system but I just don't see the wording.

 

[kwired]

Thank you for posting those Mike.

What doesn't make sense to me, and it's probably as plain as the nose on my face, is why IF we have a metallic water piping system as contemplated in 250.104(A) it matters not whether the piping is "likely to become energized".

If we have an incomplete (separated by a piece of plastic) metal water piping system 250.104(B) is only concerned with the bonding of the metal portion that is "likely to become energized".

Why the distinction?


Pete

What makes a pipe likely to become energized? Maybe an electric appliance that also attaches to the pipe somehow. What is wrong with the EGC for that appliance to bond that section of pipe? 250.104 A 1 says the bonding jumper must be sized to 250.66 for the metal water piping system. If it is not considered a metal piping system then it must be other metal piping mentioned in B - but B uses that word system also, so I guess it is just an isolated section of pipe that is not really addressed by the NEC. That gets back to the question of how much metal piping vs non metallic piping before it is no longer a system? If you have just one device like a water filter or water softener that breaks continuity does that disqualify the rest of the system that is metallic from being called a metal piping system?

 

[jwelectric]

There is no requirement to make a metal piping system electrically continuous. If for any reason someone feels that a jumper should be installed somewhere to ensure continuity then the piping system must not be a complete metallic system and would fall under 250.104(B)

 

[iwire]

There is no requirement to make a metal piping system electrically continuous. If for any reason someone feels that a jumper should be installed somewhere to ensure continuity then the piping system must not be a complete metallic system and would fall under 250.104(B)

Is this a code fact or an opinion?

 

[kwired]

There is no requirement to make a metal piping system electrically continuous. If for any reason someone feels that a jumper should be installed somewhere to ensure continuity then the piping system must not be a complete metallic system and would fall under 250.104(B)

The requirement is to bond the system. If you have an all metallic system except for one non metallic water filter isn't both sides of the filter still part of the system they are just electrically isolated.

250.104 B still has the words "piping system" just like 250.104 A does.

B does use the words 'likely to become energized' and allows you to size the bonding jumper to the circuit likely to energize the piping and 250.122 instead of using 250.66.

A specificially states water piping, B says other metal piping. If it is water piping I think you have to use requirements in A. It also has no mention of potable water, waste water, heating water, etc. just water piping.

Now if you have a system with nearly half metallic and the rest non metallic piping I think it is up to the AHJ to decide if this is a metallic piping system - NEC does not define what is a metallic piping system and what is not.

 

[LarryFine]

... they are just electrically isolated.

Are they? I believe that's the real question.

In my opinion (my opinion, guys), it would be just about impossible to electrically-isolate the hot half of a "mostly-metallic" domestic water supply system.

Has anyone here ever actually experienced, or tested and found, an isolated hot half of a water supply?

I know of two places in my house where the hot and cold copper pipes cross, and are soldered together to prevent damage from movement. My water heater has no jumper.


Added: Since we're already limited in which part of a piping system we can land the GEC on, the concern really is the hot half when the water heater is removed, or installed with isolation.

Since energization from the GEC isn't the concern (and I agree with bonding around removable water-main devices), what would be the source of energizing the hot half of the system?

 

[jwelectric]

Is this a code fact or an opinion?

Well Bob can you show a requirement that the metal pipes are required to be electrically continuous? If not then I would assume that there is no such requirement especially sense it was once very clear that the metal pipes were once required to be electrically continuous as outlined in this 1975 code section

Yes this requirement has been removed for many years now and I don?t think anyone can point it out in any of the codes sections of today, can you?

 

[jwelectric]

The requirement is to bond the system. If you have an all metallic system except for one non metallic water filter isn't both sides of the filter still part of the system they are just electrically isolated.

No if they don't have electrical continuity then they can not be all metal

The rest I refer you to the panel statements of the above proposals

 

[LarryFine]

It still says "that may become energized" which I translate to mean likely.

 

[iwire]

Well Bob can you show a requirement that the metal pipes are required to be electrically continuous? If not then I would assume that there is no such requirement especially sense it was once very clear that the metal pipes were once required to be electrically continuous as outlined in this 1975 code section

Yes this requirement has been removed for many years now and I don?t think anyone can point it out in any of the codes sections of today, can you?

So as always you refuse to just answer the question. I figured as much when I asked it.

What is funny is that I have not stated my position on this issue and you seem to be assuming that you know my position.