Dissimilar metal problem ?

Old 10-26-17, 09:21 AM
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Location: Northern Minnesota
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Dissimilar metal problem ?

This isn't in use at the time and probably won't for some time by the looks.
If I did it it's ~30 years ago, the other guy then ~40 years, I don't remember.

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This is copper coming down from a sweated valve inside the house. It looks
like the copper has 2 flat sides that I could put a wrench on to hold it while
removing the galvanized elbow, at least that's what I think it is.

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You think this will turn without ruining the copper? I could spray the top
of it with PB Blaster a few times over the winter if that'll help. Very little room
under there, not easy to get at.


Old 10-26-17, 09:31 AM
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If your replacing the ell then just cut the copper.. You need to put brass on the other side and not copper directly into galvanized..

If you get it out best bet would be a brass ell..
Old 10-28-17, 03:34 PM
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Thanks Mike, you had me thinking of another way. I don't think there is enough good pipe cause the electrical ground is right above then we have the floor.

Brother's Plan B:

Here's from the inside:

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He suggests I cut just above the old valve then this:

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Pipe to valve is 7/8: OD so I'll reduce it to 3/4" screwed into the ball valve. Below the valve I'll use soft copper with a easy bend below the floor to eliminate the elbow down there.

QUESTION: he says if the pipe above the valve is 7/8" OD that means I need a 3/4" sweat to male pipe. I'm thinking I need a 1" solder to 3/4" pipe reducer like in the picture.

I could be wrong, sure wouldn't be the first time.

Thanks and any better suggestions welcomed, won't be doing this till spring.
Old 10-28-17, 04:19 PM
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He is correct..... 7/8" OD requires a 3/4" connector.

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