Fixing Your Plumbing To Fix Your Life

How to Repair a Leaking Copper Pipe With a Soldered Slip-Tee

A lot of homeowners are unsure of themselves when working with copper plumbing, but there is no need to be afraid of performing basic repairs such as fixing pinhole leaks. If you have recently discovered a small leak in a copper water line, then you can successfully make the repair. All it takes is a little know-how and using the right tools and materials for the job. Below is a list of what you will need as well as a procedure for the fix:

Tools and materials needed

  • Copper slip-tee—Choose the appropriate size for the pipe diameter you are repairing, and be sure the opening on the odd side of the tee is threaded for a screw-on cap.
  • Copper screw-on cap—Select a cap that will screw onto the slip tee's threaded opening.
  • Silver solder—Do not use lead solder or any solder not rated for use with potable water lines.
  • Solder flux—Purchase flux designed for use with plumbing applications and silver solder.
  • Fine grit emery cloth strip—If you don't have emery cloth available, you can use a 400-grit piece of sandpaper cut into a 1-inch wide strip.
  • Adjustable groove-joint pliers—Be sure to use a pair of pliers that are large enough to easily grasp the pipe you are handling.
  • Tubing cutter—A hacksaw may also be used, but you will need to be extra careful not to damage the surrounding plumbing.
  • Propane torch and bottle—Torches using electric ignition are easier to handle when performing repairs.
  • Scratch awl—As an alternative, almost any sharp-pointed tool or knife made from hardened steel can be used to mark the softer copper.

Step-by-step procedure

1. Cut away the leaking section of the copper pipe. Once you locate the leak's origin, turn off the water supply, and mark the leak location using a scratch awl or other sharp tool. Next, hold the slip-tee up to the section of the pipe, and center the tee over the hole. Mark the copper pipe adjacent to the ends of the slip-tee with the awl.

After marking the pipe, measure approximately one-half inch inward from the marks you made and make additional marks; these final marks will show you where to make your cuts in the copper pipe. Adjust the tubing cutter blade until it slips easily over the pipe, then align the blade with the cutting mark. Slowly tighten the blade and rotate the tubing cutter around the pipe at the same time. Continue the cycle of tightening and rotating until the blade cuts through the copper. Repeat this process with the opposite cutting mark and remove the leaking section of pipe once the cutting is finished.

2. Prepare the ends of the copper pipe and slip-tee. After the bad section of pipe is removed, you will need to clean the ends of the pipe with a strip of emery cloth or fine-grit sandpaper. Vigorously sand the pipe to remove any signs of oxidation or pitting; the copper should be as clean as possible to prevent possible leaks.

Next, use the emery cloth or sandpaper to roughen up the inside of the slip-tee at both ends. Avoid permitting oil or grease to enter the workspace, and be sure to wash away any contamination with soapy water before proceeding.

3. Apply solder flux to the pipe ends and slip-tee openings. Using the brush that comes with the flux, apply a thin layer of flux to the ends of the pipe and slip-tee. Do not use too much flux, as it can cause pitting or burning of the pipe when heated.

4. Solder the slip-tee in place. After applying flux, light your propane torch and adjust the flame, so it projects a small, blue tip. Don't use a large flame, or you risk causing a fire or overheating the pipe. Next, position both pipe ends to maneuver the slip-tee into the open gap, then push the pipe ends together to hold the slip-tee in place with friction.

Uncoil a couple of inches of silver solder, and hold the free end with one hand. Keep a tight grip on the solder roll to prevent it from unraveling once the pressure is removed. Now, apply the blue flame tip to the slip-tee next to its junctions with the pipe. Heat it for several seconds, then lightly touch the heated joint with the tip of the solder; once the joint is hot enough, the solder will melt and stick on the pipe.

As you continue to heat the pipe, move around the circumference of the pipe and touch the tip of the solder to the joints between pipe and tee. Notice how the solder melts and is "pulled" into the space between the tee and the pipe. Keep working the "heat/solder" cycle until you have used an adequate amount of solder to fill the gaps all the way around the pipe. Allow the pipe and joints to cool down naturally.

5. Attach the screw-on cap. After the soldering is complete and the pipe has cooled down, attach the cap to the threaded opening on the slip-tee. This opening serves as a safety valve to permit steam to escape the pipe during heating in step 4. However, once this process is finished, you should cap the pipe and use a pair of adjustable pliers to help make a good, leak proof connection.

For more information or assistance, contact services like Bishop Plumbing, Heating and Cooling.