How to Solder and Patch Copper Tubing

Repairs holes in copper tubing to keep water flowing without leaks.

Patching and soldering copper tubing becomes necessary when the tubing develops a hole or sustains other damage. Plumbers and homeowners alike use copper tubing because it is flexible, making navigation around obstacles cleaner and neater. A copper tubing wall is thinner than the wall of a copper pipe, which makes it more fragile and more likely to develop pinholes.

Things You'll Need

• Bucket
• Hacksaw or pipe cutter
• Copper coupling
• Fine steel wool or pipe brush
• Flux
• Propane torch
• Lead-free solid core solder
• Tape measure

Instructions

1. Turn off the water supply at the main valve.

2. Drain the water from the copper tubing by turning on the faucet connected to it or have a bucket handy to catch the water when severing the copper tubing.

3. Cut the tubing at the point of the hole, leak or damage with a hacksaw or pipe cutter. A pipe cutter guarantees a straight cut.

4. Move the two ends of pipe apart.

5. Measure the size of the copper tubing with a tape measure. Your copper coupling must fit the tubing.

6. Rub the tubing with fine steel wool or a pipe brush to remove burrs and smooth the tubing and inside of the coupling. Continue to rub the copper tubing until the surface is shiny.

7. Wipe the surfaces with a clean rag to remove copper shavings.

8. Apply a thin coat of flux to the ends of the tubing.

9. Insert each end of the tubing into the copper coupling.

10. Apply a thin coat of flux to the ends and ridge of the coupling.

11. Heat the joint of the coupling, using a propane torch. This takes a few minutes to heat the tubing enough for soldering. Keep the torch in constant motion over the tubing, moving back and forth at all times to avoid damage from a direct flame.

12. Turn the propane torch off.

13. Touch a piece of lead-free solid-core solder to the joint on each side of the coupling. When copper tubing achieves the correct temperature for soldering, solder melts and runs a bead around the coupling without the propane torch flame. If the solder does not melt, continue to heat the tubing with the torch. Do not use the flame to melt the solder, only the heat generated from the copper tubing. Allow the solder joint to cool.

14. Turn the water back on at the main.

Tips & Warnings

• Keep a fire extinguisher handy when working with a propane torch.

• Work in a well-ventilated area when soldering.

• Wear gloves and eye protection approved for high heat.

References

• "Plumbing;" Time Life Editors; 1979