Plumbing: brass nipples vs. galvy nipples
 

No, this is not a hooker topic.

I've run into badly corroded galvanized nipples 3 times in the last 6 months while putting in new kitchen and bathroom faucets. The galvy nipple appears to be the weak link in the deal. They can be hard to get out, I learned from a real plumber about using reglar old easy outs, big ones, to get a corroded nipple out.

This while the same guy was helping me with a kitchen faucet. I had gotten a late start on a Sunday. It's with a new client, an 60ish widow who owns 5 or 6 large rentals, she keeps gushing about how lucky she was to find me. She pays top dollar and I want to keep her happy.

This is in an older bldg., it had one of the old wall mounted faucets, w/ no lower shutoff valves (PITA), it was a 5 unit apartment house, and I had water shut off to the entire bldg., of course.

The nipple was no longer viable, too corroded to seal at the faucet, it just did not want to come out, and I was approaching panic mode. I called my sorta plumber buddy who happened to be having dinner with his boss, an actual plumber. He offered to come over and help me, and as it was 7 pm Sunday night, I happily put aside my macho pride and said "Hell yes."

We finally got it out, had to cut a channel in it using a skinnied up sawsall blade held in a vise grip (got to be careful no to go all the way down to the threads or you can bung up your seal with the new nipple.) Then we banged it out, collapsing it on itself, or rather he did, with me holding a prybar behind it so it wouldn't bounce around. We got the hot water side out with the large easy out. We took out both so as to put in new brass nipples on each side. Disaster averted.

The question for me is: is the brass really a good idea? I mean, I know you don't join steel and copper together, as galvanic corrosion will eat the steel away in no time. When joining old galvy pipe to new copper, you use a di-electric junction. A 6 inch length of brass pipe is supposed to be good enough also.

These corroded nipples have got me wondering. Brass is part copper, perhaps galvanic corrosion still takes place, just much slower. The elbow in the wall that the nipple is screwed into has never been anywhere near as badly corroded as the nipple in my experience, so it's not just age that causes it.

I have this awful feeling that the brass nipple will just result in someone having to rip half the wall out someday in order to replace the galvy elbow corroded by the brass nipple. Who knows, might be me faced with that headache.

Of course, by that time, new copper throughout might be a good idea, but in a multi story building, that's way expensive.

Anybody know? I haven't had much luck with searching the web.

When I first bought my house I had to do a lot of repair to the plumbing and hot water heating systems. I used tons of dielectric unions between copper and galvanized. However, I have a few places in my house and in some rentals where someone joined copper directly to galvanized. These joints have been there for at least 20 years with no problems at all.
So, my experience seems to indicate that your brass nipples should be functional for many years to come.

That's reassuring. I've heard conflicting stories about galvy iron to copper before.

I don't get it. Some reports are out there that claim in no uncertain terms you'll regret it.

Then there are stories like the one you mention. I just don't get why the galvy nipple is deteriorating to iron dust while the elbow is just fine.

BTW, I lucked out big time with the plumber pro coming over to help me. Only charged me $100 and the landlady had no problem covering that. I'm going to steer work to the guy if I can. There's a lot of jobs I'm not really qualified for.

Much depends on the mineral content and ph of the water. I have low ph water- a copper to galv union won't last 5 years. Brass seems to last forever. I have swapped out most of my copper piping for c/pvc.

Is c/pvc that new Pex stuff that they use for radiant floor heating?

Jeez, I should have become a real plumber, apprenticeship and all, years ago. Radiant floor guys make serious $$.

Is regular old white PVC OK for potable water?

In your original scenario, why couldn't you have removed the elbow as opposed to removing the nipple?
I've got a couple of rentals with old plumbing like that. No shut off valves and old pipes. What I've done in the past is to bring a sawzall, cut the galvanized back from the faucet, unscrew the cut pipe put in a nipple and install a shut off for the faucet so I can turn on the water to the rest of the building when I mess with the faucet replacement. May not have been possible in this case but I'm always thinking of ways to save my ass if I start digging into that old plumbing and I have to shut off the water to the whole building.

The new Pex is different from c/pvc. If I ever do a place new or over, I'd do it in Pex.
The white pvc is OK by me for potable water. In some locations it's not, and sometimes for good reason. Check with your local building inspector.

Ahhhh! Crap! Though there was something good to read.

This sounds like a very good approach.

Tom W

I usually don't have any problems with either one. Just blast the elbow with a very good propane or acetylene torch and it expands away from the pipe or the nipple. The pipe wrench extracts the nipple or removes the elbow from the remaining length of pipe.

Heat is my friend.........I'm never on the job without it. I recently bought a relatively costly propane torch (cast aluminum) with a 3200F. flame temperature. It's fantastic.

This kitchen has a tile backsplash, and I had about 1 inch worth of corroded nipple sticking out from it. The elbow was about an inch back from the tile face. I was having a hard enough time getting a purchase with a vise grip -- not enough for a pipe wrench to grab. If I owned the building, I'd give serious thought to putting shut off valves in, but that would be a big job as well -- would have to cut out the lathe and plaster below the sink. But getting the elbow out w/o serious demolition to the tile and wall wasn't going to happen.

Hey, BC. I heated the thing up numerous times. Later it occured to me that heating it big time then quenching the nipple with cold water might make the nipple contract a bit, relative to the elbow, which is also going to get hot. Didn't think of it soon enough. At any rate, heat didn't do it.

I was getting desperate so I broke out the tile around the nipple so I could get a wrench on it. Still no go.

When my buddy's boss showed up, he used MAPP gas on it, got it really hot, still no go. He leaned on it with the easy out with some serious muscle -- no go. I was thinking the nipple was rusted to the elbow. But when we got it out, looked clean. Just in there for 30 to 50 years (or more) I'm guessing.

Replacing the tile was sort of a pain, but oh well -- I'm getting paid for it -- not like I wanted to break it out.

The thing I still don't get: the galvy nipple doesn't have any galvanizing left where the threads are cut, both ends. Both ends are in contact with water 24/7. In all the cases where I've seen this, the end at the fixture is in much worse shape than the end in the elbow.

My condolences. It didn't work for you because heating the nipple causes it to expand into the threads and tighten them further. Unfortunately, you couldn't heat the elbow..........tough situation.

They make a can of "cold shot" that might have helped you...........freeze the nipple and force it to contract from the threads. But, the temperature differential is minimal compared to the necessary contraction, so, I don't believe such an approach is going to be all that successful...........now, if you could source some dry ice...........or liquid nitrogen.........now you're talking.

The dry ice might not be a bad idea. Having it on hand would be the tough part. I know a couple of outlets for it but they're off the beaten track.

Not sure if I'm right on this, but I think I've sometimes gotten something to break free with heat even though both parts were heated and expanded.

I'm thinking the heat might make the two parts move slightly against each other, if you can heat one part faster than the other, which might break something free. Also, when the atoms/molecules are moving fast, maybe things slide against other things easier. Who knows.

I was trying to train the flame on the elbow, I could sorta aim at it, but I'm sure the whole thing got hot.

Definitely...........heat helps. But, when you heat the nipple and hope the heat gets to the elbow..........you're really praying. The nipple will always be hotter than the elbow, and, although heat helps the parts move relative to each other.........they are not moving in the right direction.

The trick is to heat it for about 15 minutes (so the elbow is hot) and quickly shove some dry ice onto the nipple to contract it...........that will surely break it loose from the threads.

At the very least, I'm going to try that with water ice some day as it is way more likely to be close at hand. I can't see stopping by to buy some dry ice every time I go to a plumbing job.