Fixing broken copper pipes might seem difficult. However, it’s a straightforward task if you know how to do it right. There are certain things that you need to keep in mind when carrying out this task.

Regardless, there’s no need to worry—this guide explores the basics of how to solder copper pipe leaks, including the tools you’ll need to complete the job safely and correctly.

How to solder copper pipe leaks

A lot goes into soldering copper pipe leaks, from cleaning pipe surfaces to cutting the pipes into pieces to applying the soldering paste onto the joints. You’ll also need to exercise a lot of caution when using the required propane torch.

Requiring this much due diligence means many homeowners usually hire a plumbing professional to do the job. Regardless, it may be helpful to understand the process. Here are the steps needed to solder a copper pipe leak.

Step 1: Assemble the required tools and materials

The first step is to get all the tools and materials needed for the job. You can find most of these at a local hardware store.

Here are the tools required for the soldering project.

  • Plumber’s tape
  • A soldering torch
  • Slip joint pliers
  • A tube cutter
  • A water bucket

Here are the materials you’ll need for the project when dealing with how to solder copper pipes.

  • A copper pipe
  • Copper fittings
  • A cloth sandpaper
  • Lead-free solder
  • Soldering fuel
  • Soldering flux

Safety tools like goggles, gloves, a long sleeve shirt, a fire extinguisher, and face protection are also crucial, as the process will require dealing with hot solder and flux.

Step 2: Turn off the water supply and drain the line

In terms of how to solder a copper pipe, the next step is to turn off the property’s water supply which leads to the pipe being repaired.

If the pipeline lacks a dedicated valve, you’ll have to turn off the main water valve. Before doing so, however, make sure to prepare a bucket of water just in case you’ll need it for an emergency while the water is off.

Drain the line using the most convenient method. For instance, if the pipe is on the upper floor, you can turn on a faucet downstairs to drain the line completely. But for pipes in the basement, look for a hose bibb below the joint you want to repair.

Open the faucets at the lowest point of your house to relieve any pressure in the system. This ensures you won’t have pressurized water in the pipes when cutting into them.

Step 3: Cut the copper pipe at the leaking point

The next step in how to solder a copper pipe is cutting the copper pipe about one foot from the joint using a pipe cutter. 

You can use the new fitting to mark the points where you’ll cut. Since there are various pipe cutters, it’s best to use a cutting tool that will make cutting more accessible, especially in confined spaces.

Now that you’ve cut the pipe, it’s time to remove the slight burr formed on the pipe’s inside edges. Failure to deburr will reduce the pipe diameter and cause turbulence in water flow. You can deburr the copper pipe using a utility knife if you lack a special tool.

Step 4: Clean the ends of the cut pipe

For how to solder copper pipe leaks, after cutting the pipes, use an abrasive pad or cloth sandpaper to clean around the cut sections until they become smooth and shiny. Also, sand the fitting inside as you did on the pipe. Thorough cleaning is the secret to creating stronger solder joints.

Once you’ve sanded the pipes, avoid touching the clean surfaces with bare hands since the oil from your skin may prevent the soldering flux from bonding the pipe fitting tightly. 

Step 5: Apply flux on the cleaned surfaces

Flux is an acid that keeps joints clean when heating the pipes. It also helps the solder stick to the copper pipes. Spread flux outside the copper pipe and inside the fitting to ensure all the clean surfaces are adequately covered.

Next, insert the pipe into the fitting and wipe off excess flux from the surface using a rag. If the pipe connection is close to a wooden wall, take precautions by placing a flame protector or a wet rag around the pipe and other flammable materials.

Don’t apply excess flux—you’ll only need a thin layer. The reason: the excess soldering flux may spread inside the pipe when heated, and if left for some time, it can slowly eat up the line and cause additional problems.

Step 6: Apply the solder and heat 

The next step in how to solder copper pipe leaks is actually soldering the pipe connection. But first, figure out the amount of solder to use in your pipe and the heating time needed to create a strong bond. The heating time and solder amount will depend on the size of the copper pipe you’re soldering.

Heat the pipe and try applying the solder until it melts and gets sucked into the joint. Remove the torch immediately after the solder begins to boil. Move the solder around the pipe’s circumference as it melts and wicks into the gaps.

Step 7: Let the joints cool, then test for leaks

Once you finish soldering, allow the joint to cool on its own. Don’t use a wet rag to accelerate the cooling process, as doing that may cause the solder to crack, potentially causing a leak. Instead, wait for the joint to cure itself to avoid further problems.

Finally, test the pipes for leaks by turning the closed faucet back on. Then, open the water valves slowly and check if the joint is leaking. If there’s no leak, the job has been successfully completed. 

Let J. Blanton Plumbing help you

Soldering copper pipe leaks can be more challenging when you lack the required tools or materials and work in confined spaces. 

It makes much more sense to hire an expert plumber to help fix pipe leaks in your plumbing system. Thankfully, J. Blanton Plumbing is home to professional plumbers who know how to solder copper pipe leaks.

Contact us today!