I have recently completed a solder joint using a repair coupling (1") for 1/2" copper pipe for my washer. However, it appears that there is tiny leak - less than one bead of water / day. Is there a simple and easy way to fix this without a full cut/replace? NB the pipe is in the wall.

We are hoping we can gently reheat the joint and allow the existing solder to melt a little and reset itself. Other than that, we could try adding more on top (although usually a bad idea), or finally we could cut out say 2" and use a repair sleeve. It is not possible to disconnect both sides as there is no movement in the pipes.


If you can drain the pipe (heating it with water in it is mostly an exercise in futility), then yes, you could try heating it and adding more solder in place. (Which, contrary to your assertion, is not an especially bad idea.)

If not, and you really don't have space to move things, usual practice would be to cut it out and install a "detour" loop -- two L's to bring it out of the plane of the existing pipe, two more L's with a piece of pipe between them to bridge the gap, and two more short pieces of pipe to connect the L's in the old pipe to L's in the new pipe. That gives you the play in the system that you need to bring things together, by letting you make the final connection at right angles to the old pipe. (Of course the downside of this approach is that you have to make eight good soldered connections, not just two, and it costs you a bit more for the extra pipe.)

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  • Thanks for the answer! Our current thinking is to cut the coupler in place in the middle, which would allow some moving of the pipes, and remove it. Then replace it with a new one which as no stop, and resolder to complete.
    – Simon P
    Jul 22 '14 at 18:41
  • 1
    If you have enough space to do this, then you should be able to simply heat the coupler, pull it off one pipe, then pull it off the other pipe... but whatever works. As I say, I'd first assume inadequate solder and -- if you can drain it -- try resoldering.
    – keshlam
    Jul 22 '14 at 18:44
  • Sadly I chose a couple with a stop so I cannot slide it out :) We will resolder.
    – Simon P
    Jul 22 '14 at 18:47

It might work, I have done it. It is worth trying since worst case you will have to cut it out anyway. The pipe must be drained of residual water, clean the area and put a dab of flux at the leak spot. Wrap the non-leaking solder joint with a wet rag so you do not compromise it. Heat up the fitting at the leak site and be ready to dab a small bit of additional solder to the joint. Cool it quick with a wet rag. Be careful when soldering near wood framing, many a house fire starts this way.

  • " many a house fire starts this way" and with the water shut off, too!
    – DJohnM
    Jul 22 '14 at 21:45
  • @User58220, to solder pipes you have to use a torch, often in close proximity to wood framing. Experienced plumbers take precautions, novices may not appreciate the danger; hence the warning. Aug 7 '14 at 21:46
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    Uhhh... I was agreeing with you and mentioning another factor in the hazard. I usually keep a water spray bottle handy, and wet down the surroundings lightly before starting.
    – DJohnM
    Aug 7 '14 at 21:56
  • Sorry, my bad... I thought it was, like, a sarcastic comment. All good. Aug 8 '14 at 0:10
  • Good in a pinch, but maybe not the ideal solution youtu.be/8IV7oG43DZ0?t=45
    – rogerdpack
    May 2 '21 at 5:49

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