iggy2
Senior Member
- Location
- NEw England
I searched, but did not see anything related to this situation....
Multi-family building, 3 stories. Copper H/C water mains running across the basement, with copper water pipe taps which go vertical and serve back-to-back stacks of dwelling unit plumbing fixtures. Copper pipe mains in the basement are being replaced with CPVC. Copper risers (H/C) will remain, and be tapped into the new CPVC mains.
Inspector (correctly) cited a created violation of 250.104, since bonding of the metal water piping system is now lost.
We were called in to tell the plumbing contractor to hire an electrical contractor (a plumber cannot bond, IMO) to basically run a bond from one of the choices in 250.104 to each set of copper risers, hot and cold.
Plumbing engineer was a little shocked, since he has done this project repeatedly at other sites, but this issue did not come up. When he asked me about it, I looked it up, then said "yes, of course you have to re-bond the metal piping...", just to be a smart guy. State agency funding the project was also surprised. I'm not sure what, if anything, will happen at the other sites.
Inspector says a #6 is required, assuming a 20 ampere branch circuit is the largest circuit in the unit(s) that would energize the piping. I haven't looked into that logic yet (I don't know if maybe there's a 50A for a range?). My initial read is that we have to size based on 250.66, which says per the building SE conductors. If there's say and 800A service, the bond may have to be 2/0 (!!!) per table 250.66, since this does not fall under 250.66 (A), (B) or (C).
Thoughts?
Multi-family building, 3 stories. Copper H/C water mains running across the basement, with copper water pipe taps which go vertical and serve back-to-back stacks of dwelling unit plumbing fixtures. Copper pipe mains in the basement are being replaced with CPVC. Copper risers (H/C) will remain, and be tapped into the new CPVC mains.
Inspector (correctly) cited a created violation of 250.104, since bonding of the metal water piping system is now lost.
We were called in to tell the plumbing contractor to hire an electrical contractor (a plumber cannot bond, IMO) to basically run a bond from one of the choices in 250.104 to each set of copper risers, hot and cold.
Plumbing engineer was a little shocked, since he has done this project repeatedly at other sites, but this issue did not come up. When he asked me about it, I looked it up, then said "yes, of course you have to re-bond the metal piping...", just to be a smart guy. State agency funding the project was also surprised. I'm not sure what, if anything, will happen at the other sites.
Inspector says a #6 is required, assuming a 20 ampere branch circuit is the largest circuit in the unit(s) that would energize the piping. I haven't looked into that logic yet (I don't know if maybe there's a 50A for a range?). My initial read is that we have to size based on 250.66, which says per the building SE conductors. If there's say and 800A service, the bond may have to be 2/0 (!!!) per table 250.66, since this does not fall under 250.66 (A), (B) or (C).
Thoughts?
