Fix a copper pipe leak

Question

I have a copper T joint that is leaking on one side, what is the best way to repair this joint that does not involve cutting the joint out and starting over?

-- Update --

The pipe in question is for hot water and is soldered together.

Answer 1

Nothing needs to be cut, barring a very strange installation. Unions in soldered copper pipe sytems are extremely rare, and there's good reason for that.

Applying more solder and flux without disassembly (note: not cutting) is unlikley to work.

Assess your ability to use a torch without burning the house down - a plumber is a lot cheaper than even a small fire. If you pass that test, drain the pipe, leaving the nearest taps open (don't want any steam pressure to build up) apply flux, apply heat, and pull on the pipes. There is nearly always enough give in the piping system to allow joint disassembly. If present, a few clamps of the "hold pipe to wall" type may need to be loosened to provide that give.

With the pipes apart, clean the joint surfaces inside and out throughly. Start with a damp rag in a gloved hand to wipe off as much solder as possible when the solder is still molten from heating to pull it apart. It may be worth using a new Tee, but even on new fittings, clean the surfaces throughly - it's essential to getting a good solder joint. Apply flux, reassemble. Apply heat to the joint GENTLY and dab with the solder (not in the flame - to the pipe/socket interface) watching for the point where the pipe/fitting melt the solder and pull it into the joint. Excessive heat is BAD, and can only be solved by disassembling and cleaning again.

Answer 2

If this is soldered copper slip joint fittings there really is no other choice other than cutting out the faulty parts and starting over.

Sometimes when undertaking a repair like this it can be advantageous to incorporate a UNION fitting into the line to permit the last connections to be joined together. A union fitting looks like this.

When assembling the union into the piping system do not forget to slide the brass nut part onto the pipe before soldering the unthreaded coupling part onto the pipe end.

Answer 3

If the real reason you don't want to cut it out is because you don't want to solder anything back in, consider something like Sharkbite connectors. These connectors are snap-on fittings for copper pipe. You just cut out the bad section of your copper pipe and replace it with equivalent Sharkbite fittings. It's almost as easy as Legos.

Answer 4

I am assuming you have a pin hole leak and the pipe is holding water. Not gas.

If the leak is small, a drip, and it's located on one of the arms of the T, you could potentially wrap the arm with gasket rubber and put a hose clamp around the gasket material. This is a temporary fix and the only correct way to fix this is to replace the T. But since your requirement is to do it without cutting the pipe either do it this way or via the method described in the first comment (drain and solder). Make sure you cut a piece of gasket rubber large enough to wrap the entire circumference of the pipe and wider than the hose clamp you're using. If the pin hole is directly opposite the intersection of the T, you might have to drain and solder as you won't be able to apply pressure with the hose clamp.

Answer 5

There is no 'best way without redoing the connection', unfortunately.

Ecnerwal has the most affordable solution. Disassemble and re-sweat the joint. Easy for a plumber. Certainly doable DIY, but, personally, I find it a bit of a pain. You're often dealing with fire in a confined space and you have to make sure everything is absolutely dry to work on it.

For repairs and small DIY plumbing, I really prefer the Sharkbite products that longneck suggests for a number of reasons:

• they work with copper and PEX
• you don't need the line to be perfectly dry
• the connectors allow the pipes to rotate (making it a lot easier too assemble in tight spaces)
• you can easily take them apart if you screw up.

In terms of easy assembly, I'd suggest the following:

                ++ 
                || 
                || C      
                || 
               ++++
               |  |
               |3 |
               |  |
               |  |
               ++++
                || 
                || P
                || 
               ++++
      +-+     ++  |
+-----+1+-----| 2 |
+-----+ +-----|   |
  C   +-+  P  ++  |
               ++++
                || 
                || P
                || 
               ++++
               |1 |
               ++++
                || 
                || C
                || 
                || 
                ++ 

• C = existing copper (you've cut out the 'T' and a bit of the copper)
• P = PEX pipe (cheaper, lighter, and easier to cut than copper)
• 1 = sharkbite junctions to connect the copper to PEX
• 2 = sharkbite T
• 3 = sharkbite slip connector

To install, cut out the existing leaking T and back a bit to make room for all the connectors.

Install the #1s and the #3 first. Then connect the T to the #1s with PEX. Finally, connect the T to the slip connector with PEX. The slip connector is the key to making this all easy, the slip connector slides up on the copper giving you room to put everything else in, then slides back down to make the connection.

The only drawback to all of this is cost. Sharkbites cost quite a bit. You're probably looking at $25 worth of connectors there (plus $3 of PEX).

Still, that's cheaper than getting a plumber and saves a WHOLE lot of time.