Ground to copper pipe?

Hey guys… I believe I know my answer, but It’s getting late and Im trying to finish this report. I saw the ground wire coming from the panel today going to a ground rod. There was also a ground(copper wire) coming off the bus going to the copper water pipe above my head. Question? Don’t you need a jumper between the water heater pipes? Could have this been the bonding wire? Usually is aluminum right? any help would be appreciated.



unless I am reading you incorrectly you are talking about the bond that is required from metal water pipes to the grounding system. That bond is normaly Copper.



Hi Gary… Yes the bonding wire is usually copper, but I have seen aluminum as well. I guess my confusion is if you have any grounding or bonding to the water piping system, shouldn’t you also have a jumper on the water heater pipes?


Yes at some point the hot water pipe should also be bonded and many electricians do that at the water heater.




The reason many bond the HOT water and Cold Water piping is because of the advent of new plumbing the old days the plumbing faucet fittings were soft brass or simular but their was metal to metal contact which ensured ALL water piping systems as required in Art 250.104(A) and sized by 250.66 and table 250.66....

Now the problem today is many of the fittings are plastic to metal because the fittings may be plastic while the existing piping may be plastic faucet fittings…they are not piping at the faucet if everything else is plastic piping…

But if if you speak of grounding the supply water piping and it is need to connect the  #4 AWG Copper within 5' of the enterance of the water supply......

 The BONDING is a little different than the GEC issue....

Things like Unions and some valves can disrupt the process…so many will also bond to the water heater…and then jump over to the hot water pipe as well if their is a shutoff valve on the water heater that could stop this bonding…and so on…FYI…bonding the Cold at the water heater hurts nothing…jumping over to the Hot also harms nothing…heck you could even then jump over to the GAS pipe if a gas water heater also and bond it as well…

Hope this helps…

Thanks Paul and Gary…!

Thanks Paul and Gary…!

lol…just so you know what some members think of me…lol…

Ground to copper pipe? 10/22/08 4:06 PMHey Paul! YOU SUCK! You little chicken****e scumbag weasel! You suck! Go slither back into your hole! Signed, Luv Mom

There’s an easy way to fix that Paul.

I’d venture to guess that 99.9% of the time when you do see a hot-to-cold jumper at the water heater, it is not required. Some guys just put them there because they have inspectors who don’t understand the rules, or it simply gives them warm fuzzies to do so. As Paul rightly points out, the hot and cold water piping systems are already metallicly connected in 99% of homes by the shower valves, etc. The addition of a jumper is a nice value-added thing to do, but the absence of one is not in and of itself a defect unless you know that all the water ways in all the shower mixing valves are plastic. Trailers are about the only time one might see all plastic shower valves.

lots of good information…thanks guys…

I have been thinking about doing a grounding and bonding document for Nick to look at for maybe using for continuing education for the Home Inspector. In this document would be this insert:

Much confusion revolves around metal water pipes and the NEC requirement for using these pipes for an electrode and bonding the metal pipes. The requirement to use the metal water pipe as an electrode and bonding of metal water pipes are two complete and separate requirements.

In order for the metal water pipe to qualify as an electrode it must have no less than 10 feet in contact with the soil and the connection to this pipe must be made within the first five feet where the pipe enters the building. Should there be less than ten feet in contact with soil then the pipe would not qualify as an electrode but there would be no harm in the pipe being bonded.

The requirement to bond a metal water pipe has changed over the years and many of the requirements have been completely deleted from the codes. One such requirement was found in 250-50 of past code cycles where the requirement was that any metal pipe must be made electrically continuous. This requirement to keep the water pipe electrically continuous was implemented for reasons such as the permission given in 250-80 to use a metal water pipe as an equipment grounding conductor for the replacement of three wire receptacles for two wire receptacles.

As the years past the electrical code making panels realized that the requirement to make and keep a metal water pipe electrically continuous could not be enforced therefore the permission to use a metal water pipe as an equipment grounding conductor was removed as well as the requirement to make a metal pipe electrically continuous.

In the past few code cycles the requirement to bond metal water pipes has lessened to the point that if a piping system is not entirely metal then the requirement to bond can be accomplished with the equipment grounding conductor for any equipment that is connected to the pipe.

In the classroom I use slides of past code cycles to show how the codes have changed over the years concerning the bonding requirements of metal water pipes. I also explain how some of the old requirements are hard to pass away such as the thought that there must be a bond across a water heater to bond the hot and cold water pipes together.

If one would take a moment to step outside the box and look at these metal pipes it would be easy to see that there is no requirement in either the electrical or plumbing codes to make and keep a metal water pipe electrically continuous. Should there be a need to do a repair to a copper water pipe a plumber could make this repair with a nonmetallic pipe and be compliant with the plumbing code. This repair would leave part of the metal pipe bonded and the rest not bonded. There is no requirement in either code that a bonding jumper be installed around this repair. If there is no requirement to bond around this type of plumbing repair then what would be the purpose of bonding around a water heater?