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How to splice PEX into an existing copper or CPVC line



How to replace a section or all of a waterline with PEX piping

PEX piping (standing for cross-linked polyethylene piping) has become one of the most popular methods of performing DIY, medium, and large scale project.

The reason for this is that the PEX pipe is affordable, more flexible than the traditional copper or PVC piping, and is less likely to bust in freezing temperatures. As such, many people are turning to the PEX when doing upgrades and repairs to their existing pipes.

Whether you have copper or CPVC, it is relatively easy to perform a splice on an existing line. Here is what you need to do.

The Tools

Do not start your project without preparing the area for the work. Where you may have a leak in your pipes or feel that it is an emergency, not taking the proper time to set things up can result in a big mess and a ton of money lost. First, gather all the tools that you will need for the job. These tools will be:

· Plumber’s Tape

· Stab in Tee

· PEX Pipe

· Pipe Cutters

· If needed PVC Tuber Cutter

· (if working with Copper) Copper pipe cutter or Hacksaw

· Gloves

· Measuring Tape

· Flathead Screwdriver

· Pliers

Depending on the type of fastener and the type of pipes that you have existing in your home, you may not be able to use a Stab in Tee. In such cases, you will need to solder the PEX fitting to the pipe. Check with your plumber as well as your local building codes to see which method should be used, especially if the fix is to be covered or in a ceiling.

Getting Ready

Turn off the main water supply

Depending on where you live, you may require a combo wrench to turn off your water. Water can be turned off and on close to the meter (which is usually located within 5 feet of a major roadway/alleyway). If you have a well, simplify cut off the supply to the house by turning the shut-off valve.

Release the pressure from the lines

One thing which is often overlooked is the pressure of the existing water in the lines. Open up the waterlines and let the water drain out. If you are working on a water heater (which is not recommended unless you are a licensed plumber)you will want to take additional steps to ensure that there is no pressure built up in the lines.

Splicing the Pipe

When Splicing a pipe, do not cut directly on the area which is leaking. Go about an inch to 2 inches above the area and below the area. Using a magic marker (black is best) make an even line around the pipe. You do not want to have your cut at an angle.

Cut the pipe

Using either the Pipe Cutter, The copper pipe cutter, or the hacksaw cut the pipe. The key is to make a clean cut. You do not want to use a dull pipe cutter as you will get a jagged edge or in some cases cause more damage to the pipe. Do not use a hacksaw with a dull blade as you can quickly make a mess of the copper piping.

Do not bend the pipe as you cut. This is especially true if you are putting on a metal pipe. Bending the pipe as you cut can cause damage to the waterline or unseen pinches. Cut straight through and then cut the next section. Once the top and bottom have been cut then remove the section you are replacing. If needed, you can give a light tap to this area to remove it.

Measure your PEX pipe

Using your measuring tape measure the PEX piping; taking into account the fitting. If you are not using a stab in tee but connecting the pipe but a cinch clamp or a clamp ring you will need to ensure that you have a bit of overlap on the PEX pipe.

Cut the pipe accordingly

Connect your PEX

If you are using a Stab in tee then you will need to add it at this time. Do not have the tee fit loosely. The Stab in Tee (such as a shark clamp) should fit snugly and the pipe should appear as one solid continuous line. There should be no bowing. Push the PEX pipe into the tee or snap fixture. For extra assurance, add plumber’s tape around the edges of the clamp.

Those that are using a clamp should first add the Clamp to the existing pipe. Push it up but do not secure it. Secondly, add the PEX pipe to the existing plumbing ensuring that you have at least an inch to 2 inches covering the existing pipe. Do not cut along the PEX pipe to make it fit. If the pipe does not slide easily over the existing pipe it is too small.

Once the PEX is in place move the Cinch clamp over the pipe and secure. Depending upon the type of clamp you may need pillars or a screwdriver to do so.

Do you need help? Ask us

Where pex piping and implementing it into your plumbing is rather simple, you may have questions. If so please let us know. If you need the tools and kits to get started please look at our amazon page. Here we have all the tools and equipment to help you with your project. Remember, if in doubt ask a licensed plumber to assist you.

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