AHJ Grounding Electrode Requirement

[don_resqcapt19]

For many years the NEC mandated that metal water pipes be made electrically continuous but then the members of the CMP said that the electrician could not follow the plumber around every day and install jumpers when a non-metallic repair was made on a metal water pipe. The CMP also knew that the plumber was not an electrician so mandating that they make any repair electrically continuous was not justified.

So now I have installed the bonding across the water heater and along comes a plumber and makes a repair who is charged with ensuring that the system stays electrically continuous?

It is nothing more than silly.

If there is no reason to rebond the interior metal water piping system after a repair that leaves a large part of the metal interior water piping system unbonded, is there are real reason to bond it in the first place? Maybe it should be like "other metal piping systems" where the EGC for the equipment that is connected to the water piping system is all of the bonding that is required. What makes the interior metal water piping differnt from other metal piping systems?

 

[jwelectric]

Maybe it should be like "other metal piping systems" where the EGC for the equipment that is connected to the water piping system is all of the bonding that is required.

This is the CMP statement on the many proposals made concerning 250.104(A) and a piping system that is not electrically continuous.
They said if it is not a complete metal water system then 250.104(B) would apply.

The requirement to make and keep a metal water pipe electrically continuous was removed the same code cycle that the use of a water pipe to change a two wire receptacle to a three wire receptacle was removed, i think it was somewhere around 1984

 

[jwelectric]

Who? The AHJ. Permits are required, in Ohio, so the AHJ will verify proper repair. You are not allowed to cover ANY repair work unless it has been inspected.

What is silly is to say because XYZ I don't have to do something.

Why do we add a ground rod to a waterline electrode? Because the metal water line may be replaced. Why do we bond the hot/cold? Because the fixtures WILL be replaced and the water tank WILL be replaced. A hot/cold bond insures that the "piping" remains bonded.

So what does a plumbing inspector in your office do when it gets really cold and the pipe freezes and ruptures and the plumber repairs this pipe with a non-metallic repair?

Have you all adopted a pluming code that says a metal pipe cannot be repaired with a non-metallic pipe?

Does your office require the plumber to make electrical installations?

Just how is this handled?

Then just what is the outcome of the homeowner making the repair their self?

 

[jxofaltrds]

So what does a plumbing inspector in your office do when it gets really cold and the pipe freezes and ruptures and the plumber repairs this pipe with a non-metallic repair?

Have you all adopted a pluming code that says a metal pipe cannot be repaired with a non-metallic pipe?

Does your office require the plumber to make electrical installations?

Just how is this handled?

Then just what is the outcome of the homeowner making the repair their self?

All valid points. Bottom line is permits/inspections are required. Do they happen? Rarely.

Ohio:

SECTION 109 INSPECTIONS

109.1 General.

Residential construction or work for which an approval is required shall be subject to inspection by the residential building official and such construction or work shall remain accessible and exposed for inspection purposes until approved. It shall be the duty of the applicant to cause the work to remain accessible and exposed for inspection purposes but failure of the inspectors to inspect the work within three days, exclusive of Saturdays, Sundays and legal holidays, after the work is ready for inspection, permits the work to proceed.

Failure to inspect is a 'license' to proceed!

 

[kwired]

This is the CMP statement on the many proposals made concerning 250.104(A) and a piping system that is not electrically continuous.
They said if it is not a complete metal water system then 250.104(B) would apply.

The requirement to make and keep a metal water pipe electrically continuous was removed the same code cycle that the use of a water pipe to change a two wire receptacle to a three wire receptacle was removed, i think it was somewhere around 1984

I think it was at least 1990. 1987 was the code I was using when I first started in this trade and I remember being allowed (and actually installing a few times) to use a water pipe for bringing a ground to a non grounding circuit.

 

[jxofaltrds]

I think it was at least 1990. 1987 was the code I was using when I first started in this trade and I remember being allowed (and actually installing a few times) to use a water pipe for bringing a ground to a non grounding circuit.

250.130(C)?

 

[jwelectric]

things have come a long way from 1975

 

[meternerd]

I didn't have time to read all of the posts on this thread, but mention of the shocks when working on plumbing caught my attention. I work for one of the evil POCO's, so this is from a utility perspective. Since the utility does not run a separate ground wire from the transformer to the service panel, the neutral is the only intentional path back to the transformer when an imbalance of the two hot legs produces neutral current. Any interruption of the neutral will allow current to flow through any and all other paths back to the transformers. But....this is not the only source of current that could be on the plumbing system. We had a customer who called and complained about getting shocked when he or his family were rinsing their hair under the faucet of their bathtub. Suspecting a neutral problem, I measured voltage from the faucet to the drain. 120V. Wow! I had the customer turn off the breakers to the bathroom lights ang receptacles. Still 120V. Had him turn off the main breaker....120V. Now I was getting confused. I had the line crew disconnect the secondary service drop leads from the transformer. Still 120V. Apparently we had some bad pole grounds and neutrals on the distribution system that were causing current flow through the gound. I ultimately bonded the faucet, drain and any other metal plumbing pipes together. The voltage was then zero. Any PVC fittings, insulated untions, water softeners with plastic pipe, or other interruption in the plumbing continuity must be jumpered to prevent this sort of scenario.

I'm now a FIRM believer in proper bonding! Just my humble opinion.

 

[iwire]

things have come a long way from 1975

Wow ........ thanks for posting that.

I think that explains a lot when it comes to older inspectors desire to bond anything and everything.

It seems we have been moving to 'bonded by what is likely to energize it' for a while.

 

[electrimate]

Here due to the corrosive nature of the soil, all utility water pipes are plastic. My house was built in 1966. It has galvanized water pipe in the attic and down the walls. Water service comes in the house at an outside faucet, which is fed underground from the meter with PVC pipe. Until I upgraded my service panel and added a ground rod, there was nothing bonding the neutral in the service.
Here you won't get a final inspection without a ground rod. If you bury it and use a suitable-for-direct-burial connector, you had better get that inspected before you cover it up. The power company always checks to see if there is a ground rod before they hook you up as well.

 

[kwired]

Here due to the corrosive nature of the soil, all utility water pipes are plastic. My house was built in 1966. It has galvanized water pipe in the attic and down the walls. Water service comes in the house at an outside faucet, which is fed underground from the meter with PVC pipe. Until I upgraded my service panel and added a ground rod, there was nothing bonding the neutral in the service.
Here you won't get a final inspection without a ground rod. If you bury it and use a suitable-for-direct-burial connector, you had better get that inspected before you cover it up. The power company always checks to see if there is a ground rod before they hook you up as well.

You obviously live in place where freezing temperatures don't happen (which freezing sounds good today nearly a week with highs above 100 here) Water pipes are not in attics here unless the attic is a conditioned space, and supply via the outside faucet would never happen here either other than as a temporary method of supply. Buried lines are at least 5 feet deep in general or they will freeze at some time.

 

[kwired]

Wow ........ thanks for posting that.

I think that explains a lot when it comes to older inspectors desire to bond anything and everything.

It seems we have been moving to 'bonded by what is likely to energize it' for a while.

I think it is more important to bond what is likely to develop potential. I'll give you a real world example. Few years ago when we had major ice storm take down power lines all over the place, I had a rural customer that had their power restored - but the POCO had lots of primary neutral conductors still laying on ground. Systems will work, but you do have a voltage drop on that neutral because there are places where it may be open circuited and current has to flow through earth or whatever other path it can find.

Customer calls me because they are getting shocked while in bath tub whenever they touch the water faucet. To make a longer story shorter - the voltage was between the metal water pipe which was well bonded to electrical system and the metal drain pipe, which was not bonded to electrical system but was metal pipe all the way into the ground where it left the house. Metal drain pipe was at earth potential, water pipe was at elevated voltage because of voltage drop on primary neutral (voltage was there even with main turned off - it was not a neutral problem within premesis) I bonded drain pipe to water pipe to bring them both to same potential.

Even though mostly a thing of the past, nobody ever bonds metallic drain piping when they are present - isn't it "other metal piping systems"?

 

[electrimate]

You obviously live in place where freezing temperatures don't happen

Freezing pipes are rare here. As long as the pipe is one foot deep, it will never freeze. You do need to insulate the riser up to the faucet, as we do get below freezing a couple of times a year. No problem with pipes in the attic. 40 is the average low temp. in the coldest months here. Might sound nice, but that is with near 100% humidity and wind. It's normal for it to warm up to 60 or so and then rain, then plunge back down to 40.

 

[jxofaltrds]

Wow ........ thanks for posting that.

I think that explains a lot when it comes to older inspectors desire to bond anything and everything.

It seems we have been moving to 'bonded by what is likely to energize it' for a while.

I think it is more important to bond what is likely to develop potential. I'll give you a real world example. Few years ago when we had major ice storm take down power lines all over the place, I had a rural customer that had their power restored - but the POCO had lots of primary neutral conductors still laying on ground. Systems will work, but you do have a voltage drop on that neutral because there are places where it may be open circuited and current has to flow through earth or whatever other path it can find.

Customer calls me because they are getting shocked while in bath tub whenever they touch the water faucet. To make a longer story shorter - the voltage was between the metal water pipe which was well bonded to electrical system and the metal drain pipe, which was not bonded to electrical system but was metal pipe all the way into the ground where it left the house. Metal drain pipe was at earth potential, water pipe was at elevated voltage because of voltage drop on primary neutral (voltage was there even with main turned off - it was not a neutral problem within premesis) I bonded drain pipe to water pipe to bring them both to same potential.

Even though mostly a thing of the past, nobody ever bonds metallic drain piping when they are present - isn't it "other metal piping systems"?

It is not "likely" it is REQUIRED.

250.104 Bonding of Piping Systems and Exposed Structural
Steel.
(A) Metal Water Piping. The metal water piping system
shall be bonded as required ******


I guess some of you old 'installers' don't understand what can happen! :lol:

 

[don_resqcapt19]

It is not "likely" it is REQUIRED.

250.104 Bonding of Piping Systems and Exposed Structural
Steel.
(A) Metal Water Piping. The metal water piping system
shall be bonded as required ******


I guess some of you old 'installers' don't understand what can happen! :lol:

If you are talking about the drain piping system, it is my opinion that would be covered 250.104(B). That section only requires bonding for "other piping systems" that are likely to become energized. In my opinion it is not likely for the drain pipe to become energized. Under older codes the wording was "may become energized" and if that wording was still in the code I would say that the drain pipe would have to be bonded, but not under the current code wording.

 

[jwelectric]

Wow ........ thanks for posting that.

I think that explains a lot when it comes to older inspectors desire to bond anything and everything.

It seems we have been moving to 'bonded by what is likely to energize it' for a while.

Here is a proposal from the 2008 code. Notice what the code panel's statement is;
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

George recieved a simular answer to his proposal

 

[don_resqcapt19]

Mike,
The panel statement says it applies to complete water piping systems. If there is a "cold" water system and a "hot" water system, is either one covered by 250.104(A), or are they both covered by 250.104(B)?

 

[jwelectric]

Mike,
The panel statement says it applies to complete water piping systems. If there is a "cold" water system and a "hot" water system, is either one covered by 250.104(A), or are they both covered by 250.104(B)?

They are both part of the potable water system not two different systems.

In a residential setting it is possible to have potable water system, gray water system, and a waste water system. The hot and cold are part of one water system.

 

[kwired]

In my story about the metal drain piping system, the drain piping may not be considered by some as likely to become energized. But it obviously was a good (good enough anyway) grounding electrode to become different potential from other objects bonded to electrical system grounded conductor. This was one of those instances where a person barefoot outside touching a sillcock, the air conditioner condenser unit, or some other object bonded to electrical system probably would have been shocked, but it also was early winter and the likelihood of that was not going to happen for at least 3 or 4 months.

If same thing happens in or near swimming pool everything is bonded together and there is nothing within users reach that can be at different potential.

Just my opinion, but if not likely to become energized it may be ok to not bond it. If not likely to become energized but is already grounded (as in part of it is buried in earth, or other effective means to bring it to earth potential) it should be bonded to the electrical system.

 

[don_resqcapt19]

They are both part of the potable water system not two different systems.

In a residential setting it is possible to have potable water system, gray water system, and a waste water system. The hot and cold are part of one water system.

What document says that you can't have a cold water system and hot water system in a dwelling occupancy? I see them as two water piping systems. I also do not see the gray water system and the waste water system as being covered by the rule in 250.104(A). I see those system being covered by the rule in 250.104(B).