Just wondering for now. Have an all copper plumbing. What happen to my ground if the pipes are replaced with PEX? Have two connections that I am aware of. One to the cold water pipe at water heater. The other one is ground rod by the meter.
So, what to do to the cold water ground? It is required by code here. Does that mean that PEX is not feasible?
Drive another rod 6 feet away from the existing one and connect them together with a #6 solid copper wire. That is all you need to be legal.
The ground represented by your copper pipe i the part outside underground anyway. As long as that stays copper your grounding electrode is still established.
I would assume that you would have to run a heavy gauge copper wire back to the panel ground bus. An electric WH should already be grounded however.
If you replace any segments with PEX I would make sure that any remaining copper segments are grounded. I don't know the actual code requirements but it's just a common sense good idea. Really if you have all copper it would make sense just to do any repairs in copper to maintain ground path.
Go talk to the building code inspector in your jurisdiction. Only they can give you advice that will pass THEIR inspection. When I replaced my underground water service pipe with pex I found that what the codebook said and what they'd pass were not exactly the same.
The only thing grounded to the copper plumbing in my house (built '74) was the telephone connection and it WASN'T grounded since the only part of the plumbing system actually IN the ground was the plastic piping to the well casing.
Grounding of the electrical system was accomplished through a grounding bar sunk into the ground and tied into the meter can at the service entrance.
As for your hot water heater being grounded... it is, but if properly installed, it's grounded only through the electrical service connection since the incoming cold piping and outgoing hot piping SHOULD be a dielectric fitting that isolates the hot and cold piping from ground and each other to prevent electrolysis.
The metal plumbing system of the house by code needs to be bonded to the electrical system ground. The telephone line installed used the metal piping of the house, which in turn is bonded/grounded back to the electrical system. That's how it should have been done, anyway, so I doubt the telehone line is not grounded. And if it isn't done as described above, it's dangerous and should be fixed.
And there' no bonding over to the metal water pipes of the house?
I think whether code requires dielectric unions varies by jurisidiction.
For the reason that you raise here using water pipes as a ground is not well thought of today. It may no longer be up to code where you are. You have a ground rod by your meter. Most probably that is your ground. It doesn't hurt to have the water pipes connected to the grounding system whether they are serving as a ground also, or are separated from earth by pex.
You're right of course, I forgot about that. But the cold would also be grounded even if it's electrically insulated from the tank. And I've even heard tell about some jurisdictions wanting the hot bonded to the cold around the heater, which seems like a good idea from an electrical safety standpoint (and probably happens anyway even without a bonding wire, at least in a house where there's a metal faucet hooked to both pipes.)
As we just went through exhaustively in another thread, that isn't true. If you have an incoming metal water pipe to the house, not only is it a permissible grounding electrode, it's required to be used as one of the grounding electrodes.
On the other hand, if you mean being able to use a cold water pipe at just any place in a house as a ground to tie something to, eg CATV, sat dish, etcto ground it, for new work, that I agree is not acceptable.
It may no longer be up to code where you are.
Metal water pipes *must* be bonded to ground. It's not an option.
I failed to mention (just remembered after reading other posts) that the ground to the water heater is ran/tied into the bus bar at the breaker. The bus ground is tied into a copper ground rod.
Reason I asked is I am thinking of having some of the main runs from just under the house (3/4") to some points closer to the 1/2" faucet pipes. I was thinking that PEX may be cheaper. However, I am not that comfortable in losing that secondary ground.
If I have it correct, it's not a secondary ground, whatever you mean by that. You're talking about possibly removing a section of the existing metal water pipe serving part of the house and replacing it with PEX, correct? Like replacing a section that goes to say the bathroom? If you do that you must run a bond wire to tie the sections back together again. It's not a secondary ground, it's almost always the only ground for those runs.
There is a bit of debate about bonding around plastic sections in interior metal piping systems among the inspector community. It is not specifically required in the code. The code requires a supplemental grounding electrode (to a metal water pipe) in all cases. That is typically a rod and that means two in a practical sense. Otherwise you need to be able to prove it is less than 25 ohms to ground. These days most AHJs want a Ufer (concrete encased electrode in the foundation) on any new construction.
he ground to the water heater is ran/tied into the bus bar at the breaker. The bus ground is tied into a copper ground rod.
ust under the house (3/4") to some points closer to the 1/2" faucet pipes. I was thinking that PEX may be cheaper. However, I am not that comfortable in losing that secondary ground.
ing metal water pipe serving part of the house and replacing it with PEX, c orrect?
you must run a bond wire to tie the sections back together again. It's not a secondary ground, it's almost always the only ground for those runs.
Doesn't NEC 250.104 (A1) cover it?
(A1) Metal water piping system installed in or attached to a building or structure shall be bonded to the service eqpt enclosure, the grounded conductor at the service, the grounding electrode when of sufficient size, or to one or more grounding electrodes used.
I don't see how that would allow one to take out a 10 ft section of copper pipe in the basement that feeds through to other parts of the house, eg the second story bathroom, put in plastic and not bond it back together. That section going upstairs is still a metal water piping system installed in the building, no?
(A1) Metal water piping system installed in or attached to a building or structure shall be bonded to the service eqpt enclosure, the grounded conductor at the service, the grounding electrode when of sufficient size, or to one or more grounding electrodes used.
I don't see how that would allow one to take out a 10 ft section of copper pipe in the basement that feeds through to other parts of the house, eg the second story bathroom, put in plastic and not bond it back together. That section going upstairs is still a metal water piping system installed in the building, no?
The problem is that many DIY repairs (imagine a frozen, burst pipe) do not bond the pex. Such repairs are not subject to building inspectors. It's not just DIYers either. Some years ago I bought a replacement water softener from a large chain. They sent out a "professional". His van said Plumbing. When he was done I noticed that he had bonded the inlet pipe to the outlet pipe. Both pipes were pex. He and his helper didn't have a clue.
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