[B]Soldering 101 Question[/B]

I have a bad solder joint in a 1/2-inch copper line, at a coupling. Pin-hole spray of water. There are convenient shut-off valves to isolate the section of line, but the pipe is full of water. I think I have to cut the line, drain the water, and then re-fit and re-solder. Is that right?

soldering

You are right and I think it would help you if you bought a copper x copper x female adapter tee. Solder the tee in then use a brass pipe plug to close it up. Your probably talking 1/2" or 3/4" pipe.

Did you by chance solder that joint with a "closed" system (i.e., with all the shutoff valves closed)? I recently learned on this forum that you should only solder when the pipe you're working with is open or else the pressure from air expanding when heated may cause a leak.

If you follow plumber1's advice about the tee, and of course orient the tee with the threaded side down, and leave the plug off when you solder, that should work.

Yes, Plumber1 and SteveW, I think you've got it right. I did solder the coupling into a closed section (closed by the two cut-off valves). And I agree, that's why I have the leak now: the stea/air pressure during the last soldering must have created the pin-leak I'm now dealing with.

I like your suggestion to use a Tee and a threaded plug, and will proceed with this plan. Ingenious! Thanks to both of you!!

You should be able to open a faucet, shower valve, hose bib, or something to not have a closed system.

That way you won't need a T.

If you go with T you may want to consider getting 1 that you can put a pressure gauge into if it is in your basement and readly accessable.

If your on a crawl space just plug it.

Job successfully completed, using a Tee adapter and threaded brass plug. I didn't need install a pressure gauge, but if I ever decide I want one, I know where I can install it, easily. I learned something - thanks to all of you.