How to Solder Ball Valves

Ball valves are commonly used in plumbing. They are installed in the hot and cold water copper lines so if you have to do a repair job like changing the faucets on a sink or taking out a sink to put a new one in, you don't have to turn off the water to the entire house. You just turn off the ball valve on the water lines leading to the work project.The handle of the valve is connected to an internal ball that has a hole running through it. When the valve is in the open position the hole in the ball is lined up with the opening in the copper pipes on either side of it. When the ball valve is in the closed position the holes disappear from in front of the pipe openings and no water can flow through. Soldering in a ball valve is no different from soldering a regular copper joint. Here is how to solder in a ball valve on a new copper water pipe installation.

Step 1

Dry fit the copper piping on either side of the ball valve.  Pull the copper pipe out and clean it.

Use Emory paper to sand the outside of the copper pipe until it's bright and shiny looking.  Push a wire-fitting brush into both ends of the ball valve and twist it around to clean the inside of the copper tubing of the valve.

Step 2

Brush paste flux on the outside of the copper pipe and the inside of both ends of the ball valve. 

Step 3

Push the copper pipe ends into the ball valve.  Before starting to solder make sure the ball valve is in the open position.

This means the handle of the ball valve is parallel to the copper pipe. 

Step 4

Light the propane torch.  Hold a spool of wire solder in the non-dominant hand.

Start heating up the copper pipe where it enters the ball valve on just one side.  Watch the flux.

When it turns brown and gooey in appearance and starts to bubble the metal is getting hot enough for the solder to flow.  Touch the tip of the solder wire to the seam and watch for it to melt and flow completely around the seam.

Repeat on the other side of the valve. 

Things You Will Need

  • Copper pipe
  • Ball valve
  • Wire-fitting brush
  • Emory paper
  • Paste flux
  • Flux brush
  • Propane torch
  • Wire solder


  • When the copper pipe and ball valve have cooled completely, take a paper towel and wrap it around the pipe where it meets the valve and rub vigorously to clean the excess flux off the pipe. Do this on both sides of the valve. If you don't clean off this flux, the acid in it will eventually eat through the copper and create a leak in the pipe.


  • Don't forget to open the valve before starting to solder. If you don't you will ruin the internal seal on a brand new ball valve. You will have to unsolder it and throw it away.

About the Author

B. Ellen von Oostenburg became a full-time writer a decade ago. She has written features for local and state newspapers, as well as magazines, including Milwaukee Magazine, Wisconsin Trails and German Magazine. A graduate of the University of Wisconsin - Madison, von Oostenburg holds a Bachelor of Science Degree in fine art.

Photo Credits