Shower valve threaded connection slow leak

Hello, lots of good information and opinions here, thought I would post a question regarding the leaking threaded connection pictured in the attachment. It leaks at about 1 drip per 5-10 minutes, never building up any more moisture than wetting the horizontal cut of the notch in the framing below it. You can see the drop waiting to fall in the picture. I have left it alone for a couple weeks and it remains a leak at that pace. When I put the thread/sweat connections on the valve I tighten each one with equal force, and about as much force I could put on it with my vice/wrench setup. The 3 copper adapters threaded fully and are just fine. The 1 brass elbow left me wondering if it was adequately threaded but I just couldn't get enough force for one more full turn on it. Of course it leaks. Should I have used pipe dope not tape on that connection? How would you go about solving the leak? Or would you leave it? Thanks.

Belt and suspenders...use both pipe dope and teflon tape. Note, when you solder so close to a taped joint, it can get hot enough to mess up the teflon, but the pipe dope should be okay. It'll be a pain getting that back apart...but then, you probably knew that.

I prefer to only use dope on those connections. When you are soldering that close, sometimes the tape suffers.

You can't leave the leak. You may want to insert a street 90 fitting into the end instead of using threaded connections. Often they have both the male thread and the insert for copper.

A plumber would NOT have screwed the fittings to the valve, because those connections allow us to solder the copper tubing directly INTO the valve, which eliminates any posibility of a thread leaking. But if I had used those adapters, I would NEVER have used tape. EIther redo it the way you have it, or remove the elbow and solder a copper sweat street ell into the valve, but do NOT just leave it leaking.

Who called me on not being a plumber? You're right. The answer to how long do you have to wait for this to stop leaking on it's own is 3 weeks, no more dripping. Now who would take it apart? It seems I can't get enough heat on the valve with a propane torch to get a proper solder, especially in this case with the wood and abs so close. And, not being a plumber, I'm not sure where the line of 'too much heat for the valve seals' is. I appreciate your thoughts.

Well born free, sometimes when the joints are just too close to wood or ABS, you remove the fittings and valve to an area free of wood, do the soldering there, and then bring your pre-fabed plumbing back and finish the job.

Copper MAY eventually corrode enough to stop the leak, but why take a chance.

1. You will NEVER get it hot enough to take it apart if there is ANY water inside the pipe.
2. Cut the horizontal line between the stud and the shower riser.
3. Then cut the copper above the elbow so you can unscrew it.
4. Remove the valve stem from the integral stop.
5. Insert a piece of copper INSIDE the connection after cleaning and fluxing both pieces.
6. Repipe up to the cut pipe and reconnect with a coupling.
7. Solder everything together, the open stop will prevent pressure build up.
8. Put the stop back together.
9. Turn on the water.
10. As far as the female adapter screwed onto the cold water inlet, you might want to change it also, using the above instructions.
11. Close up the wall.

Thanks for taking the time to write your thoughts, I appreciate it and maybe someone else will too. In this case; after about 3 weeks of 1 drip every 5-10 minutes there was enough corrosion to stop the leak, not a drop for a week now. Look at it now and you would have no idea it ever leaked, but that brass elbow does look suspiciously not fully threaded. I understand a plumber would rather sweat the valve connections, no expensive brass elbows, greater install time, and no threads leaking after you put about everything you could on the connection with an 18" wrench and the valve in a vice. Next time joint compound and teflon, indeed. All threads as I want to be able to relocate that valve at a later date should it become desired, which it may, or may not, but the possibility is there.

And this is one more reason that plumbers are worth their weight in gold.
Neither hj or I would have let that thing drip for three weeks. For starters, it would have been soldered, so no leak.
And if there had been a leak, it would have immediately been removed and redone until there was no leak, before we ever left the job.
No call backs, that's the rule.

I doubt if the leak stopped because of any corrosion, but rather calcium and or debri build up at the threads. Its called natural pipe dope!

Whether or not you are a dope to trust it is another question. I had a few in life and they always stayed shut after plugging up.

I would have done it all in pex in 1/8 the time and had no leaks at all. And with a leak, a fix is just a pocketknife away.