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Water heater grounding

K

Karencita42

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Joined
Jun 27, 2022
Messages
24
Location
Miami, Fl
Good morning all,

I have a 30 gallon water heater and will be replacing it with a tankless water heater. The 30 gallon water heater has two grounds attached to the inlet copper pipe. The unit itself is also grounded via the ground running from the breaker to the tank with the two other hot wires.

What do I do with the grounds attached to the copper water pipe? Do I need to reground those or just disreagard as the 8 gauge wire has a ground already.
 
If the building has copper piping, the copper piping needs to be grounded (bonded) with the separate wire per the National Electric Code 250.104(A). The ground wire coming from the panel is called an "equipment grounding conductor", and while it is connected to the water heater that is connected to your copper piping, the various connections from the water heater to the copper piping are not considered to be good enough to ground/bond your copper plumbing. Depending on the size of your electric service, the ground wire(s) attached to your water pipe might need to be a different size than the equipment grounding conductor for your water heater.

I would just leave the ground wires attached to the water pipe alone. If they are in the way, you can move them to a different section of the pipe.

If your plumbing is nonmetallic, such as PEX or CPVC, then there is no reason to ground/bond it at all.

(Insert appropriate warnings about using licensed professionals and observing all local codes etc...)
 
Beniah Naylor said:
If the building has copper piping, the copper piping needs to be grounded (bonded) with the separate wire per the National Electric Code 250.104(A). The ground wire coming from the panel is called an "equipment grounding conductor", and while it is connected to the water heater that is connected to your copper piping, the various connections from the water heater to the copper piping are not considered to be good enough to ground/bond your copper plumbing. Depending on the size of your electric service, the ground wire(s) attached to your water pipe might need to be a different size than the equipment grounding conductor for your water heater.

I would just leave the ground wires attached to the water pipe alone. If they are in the way, you can move them to a different section of the pipe.

If your plumbing is nonmetallic, such as PEX or CPVC, then there is no reason to ground/bond it at all.

(Insert appropriate warnings about using licensed professionals and observing all local codes etc...)
Click to expand...
Thank you very much. The majority of the home is with pex and some cpvc. The only piece of copper was the actual shutoff valve and about 18 inches of copper pipe leading to it, that were joined to the cpvc from the wall.

Thank you so much.
 
Replace it with PEX and sell the copper - anymore 18" of copper pipe and the ground wires attached to it might buy you lunch, lol.
 
Karencita42 said:
Good morning all,

I have a 30 gallon water heater and will be replacing it with a tankless water heater. The 30 gallon water heater has two grounds attached to the inlet copper pipe. The unit itself is also grounded via the ground running from the breaker to the tank with the two other hot wires.

What do I do with the grounds attached to the copper water pipe? Do I need to reground those or just disreagard as the 8 gauge wire has a ground already.
Click to expand...
The two ground connections raises a question. Without going into the why of it, I suggest that you look at the water main where it enters the building to find out if the yard pipe is metallic. And if it is metal pipe that there is a grounding electrode conductor landing on the pipe.
 
ICE said:
The two ground connections raises a question. Without going into the why of it, I suggest that you look at the water main where it enters the building to find out if the yard pipe is metallic. And if it is metal pipe that there is a grounding electrode conductor landing on the pipe.
Click to expand...
Thanks
 
ICE said:
2 GPM is not much and 50 amps is plenty.
Click to expand...
2 GPM will give you one shower while someone else washes their hands. If someone lives alone, 2 GPM might work but for a normal house, nowhere near enough. Plumbers like selling them but to keep the price down they sell small ones like this that don't deliver the needed GPM.
 
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