Will anything stop a VERY slow water leak under pressure?

[Chuckhead]

I have a VERY slow leak in a threaded joint in a hot water heating pipe (copper).  Maybe 2-3 drops/day.  I can't tighten it because the other end is soldered into a T.   I would like to avoid having to drain the system, cut the pipe, tighten the threaded joint, then re-join where I cut it.  I couldn't do that right now anyway because it's heating season.  Is there anything I can apply now that will stop the leak, preferably permanently?  Nothing I've tried works.  JB Weld for plumbing with several coats of oil based paint seemed to have fixed the problem, but after almost a month the drip re-started.  I'm sure part of the problem is that it's a heating pipe that expands and contracts frequently.  Any ideas would be appreciated.  Thanks.

[Stwood_]

Sometimes the minerals in your water will plug small leaks, given enough time.

[jteneyck]

Sometimes the minerals in your water will plug small leaks, given enough time.

This has worked for me several times, even on my boiler.  I put a rag around the joint to keep it from dripping until the minerals close off the leak.  

John

[arthropod98]

i know you mentioned JB weld, but this is the one i've used with really great results:

https://www.jbweld.com/product/steelstik...utty-stick

[gear jammer]

If it's a heating pipe and not potable would Bar's leak or Stop leak like what is used in a car radiator work?

[blackhat]

Nothing short of the correct repair will stop it. Bars Leaks is a good way to bugger all the air vents in your system.

[Oldwood2409]

[quote pid='7919172' dateline='1604958900']
Old pipe fitter trick. Only it will make the threaded joint trash after you do this. Take a small chisel (not a wood chisel) and peen the threads on the pipe with the thread of the fitting. Hope this helps
[/quote]

[Snipe Hunter]

Nothing short of the correct repair will stop it. Bars Leaks is a good way to bugger all the air vents in your system.

Thank you

Just fix the dang thing

[Chuckhead]

Thanks everyone for the ideas.  Sounds like my best bet is to just put something under it to catch the drips and let it sit until spring.  If the Plumbing Gods are on my side (yeah, right 
), the minerals in our very hard water will have plugged the drip by then.  If not, I'll drain the system and fix it the right way.

[Robert Adams]

Like mentioned if it's small enough it will seal up on it's own. It's very common in industrial settings to not worry about those tiny weep leaks as they stop over time on their own.