Do I or Don't I

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Dennis Alwon

Dennis Alwon

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Retired Electrical Contractor
If a solar water heater, with copper water lines running through it, is installed on the roof of the house and a short section of copper enters the attic then connects to pecs (plastic pipe) , then do I need to bond the copper.

Art. 250.4(4) says electrically conductive material likely to be energized-- I don't think this is likely to be energized. However 250.104 (A)(1) seems to suggest otherwise. Can you help this old man???
 
that's not a metal water piping system, its a solar heater with metal pipes attached to a plastic water piping system (jmo)

if it was on the roof I'd be more inclined to attach it to a lightning rod anyway (I'd be afraid the interior conductor would light up the house if the roof got hit)
 
nakulak said:
that's not a metal water piping system, its a solar heater with metal pipes attached to a plastic water piping system (jmo)
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That was my feeling on it but I had a friend saying otherwise. I cannot see how it can get energized anyway--
 
Dennis Alwon said:
However 250.104 (A)(1) seems to suggest otherwise. Can you help this old man???
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Also says to size for the circuit likley to energize it. How would you size that?
 
chris kennedy said:
Also says to size for the circuit likley to energize it. How would you size that?
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It says to bond according to 250.66.

Also, if you have plastic pipe from the well and then have a copper system in the house you would have to bond the water lines. I am not sure how this is different. There is just more plastic before the copper.
 
This requires bonding as much as the copper flashing around the chimney does. I haven't seen to many bonding conductors attached to the flashing.
 
I look at that just like a tanked hot water heater. If the house is run in pex, at the water heater many times they'll change over to copper pipe going into the heater. I've never bonded that, so I wouldn't bond the solar system either.
 
Bonding or Grounding of A Solar Panels Piping ... hmmmm.
This sounds like a good topic to bring before the commitee members assigned to the next NEC code update for 2011 !
I personally believe,as nakulak had mentioned,that I would be inclined to attach the copper to a ground rod myself.That amount of copper on the roof would almost certainly draw the lightning to it and I'd rather have it follow a safe path to ground than just light up my roof (fire) during a storm !
Than again,that's just my opinion.

Carl
 
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Carl Ewing said:
Bonding or Grounding of A Solar Panels Piping ... hmmmm.
This sounds like a good topic to bring before the commitee members assigned to the next NEC code update for 2011 !
I personally believe,as nakulak had mentioned,that I would be inclined to attach the copper to a ground rod myself.That amount of copper on the roof would almost certainly draw the lightning to it and I'd rather have it follow a safe path to ground than just light up my roof (fire) during a storm !
Than again,that's just my opinion.

Carl
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I didn't know lightning was attracted to copper....
 
When I had a similar system removed from my house, the plumber did not seem to notice any attached wiring (i.e., bonding wires). I am sure he would have said something about getting the wires removed, before he could finish the piping removal.

But then, perhaps you shouldn't use my house as an example of previous ownership following electrical rules. As I mentioned several months ago, I had a wall-switched, permanently installed overhead light in a hallway that had gotten its power from a cord plugged into the wall. Actually, I discovered this situation after the plumber had removed the water tank associated with the solar panels. ;)
 
I just got off the phone with our NC state inspector and he says that the state considers a water piping system to be bonded if 51 % of the piping is metallic. The NEC is not clear what a water piping system is so that have used that as a guideline.

The whole thing sounds strange to me. If there is 500 feet of copper piping up on the roof and only 300 feet in the house then it would need bonding. Of course who is going to measure how many feet is in the collector.

It is an interesting question to me. Many of us tend to think it is a plastic system with a bunch of copper in the middle.

If I have a copper system with 30 feet of plastic in the middle does that negate the need for bonding. Is it a copper system with plastic in the middle or do both sections of copper need bonding.

I am starting to think I will bond the copper. Too many if's and I think there is room for a change in the code to clarify this area. Any takers?
 
JMO, but I think the key is the phrase "likely to be energized", not the per cent ratio of copper to plastic. I just cant see the justification from that standpoint.
 
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