I've cut out the drywall ceiling below my upstairs bath and have located the source of a water leak. It is coming from a copper sweat joint elbow in the cold water supply line to the bath tub.

Can I repair this leak by "resweating" the joint and applying new solder - without diassembling the joint? or do I have to take the joint apart and remake it new - which is VERY difficult because I don't think the can get the new elbow onto the the pipe - there's not enough play in the pipe which is connected on both ends to parts I have no way of reaching (nor can I, without cutting it, get the old elbow off).

If I can "resweat" the pipe, I had intended to drain water out of the line by shutting off the water suppply to the house and opening downstairs faucets - but this will surely leave some moisture in the pipe. Is this a problem?

 

You really need to sweat the fitting apart, clean it up, sand it, re-flux and re-solder it to repair it right.
Open the faucets above (air) and below (drain) it to allow it to drain.
Trying to re-solder it in place may work, but I doubt it.
Good Luck!
Mike

 

cut the pipe right by the elbow socket, remove the elbow then reassemble using a street elbow and slip coupling. The street elbow has a socket on one side and is the same size as pipe on the other. The slip coupling doesn't have a stop in it so it can slide completely over the pipe then back onto the street elbow.

 

Thanks for the two great replies. My friendly Home Depot had no copper slip joint connectors - only w/stops. So today I'm off to my plumbing supply house.

Thanks!!

C. P. O'Neill

 

you can take abrasive cloth or a small file and smooth down the stop inside that coupling.

 

Belive it or not, you can create slip joints by using the next size OD pipe. For example to get a fitting for a piece of 1/2" pipe, you would use a short length of 5/8" as a coupler.

 

Thnaks to all who replied. Took the afternoon off from work and tackled the leak.

The leaky connection is now repaired. I had a devil of a time trying to "unsweat" the existing joint - as it turns out, there was too much water in the horizontal leg of the pipe run which I could not get to drain. So - I could not get the existing solder to melt. So, following the advice here, I cut the pipe as close to the hub end of the elbow as I could. An amazing amount of water was still in the pipe. Used a street elbow and a slip coupling (which Lowes had, but Home Depot did not). Made up all the joints, but still had a dickens of a time trying to get the joint hot enough for the solder to flow - it wouldn't. Took joint apart again and soldered one end of the street elbow, then, having read my do-to-yourself plumbing book, used bread to stop any more water flowing into the joint. This time sucess. I could get the solder to flow into both ends of the slip coupling. Held my breath, turned the water to the house back on - and - lo and behold, the joint was good. First time I had ever seated a joint.

My wife was happy that we had water to get supper. It would not have been happy here if I had to leave the water to the house off all night and call a plumber in the morning.

Thanks to all you folks who gave me advice.