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How to Install Expansion Fittings onto PEX-A Pipe

How to Use and Install PEX-A Expansion Fittings

Like any plumbing project, your first step should be shutting off the water supply to the area you're working on. If necessary, relieve line pressure by opening a nearby faucet until the water stops flowing. For installing expansion fittings, it is recommended to use PEX-A tubing due to its flexibility and elastic memory.

  1. To begin, make sure the end of the tubing is cut square.
  2. Slide your expansion ring over the PEX tubing until it overhangs the end of your tubing by no more than one-eighth inch, or until the stop on the ring, if present, touches the tubing.
  3. Using a manual or cordless expansion tool, insert the tool into the PEX pipe and expand the pipe. Note that each PEX pipe requires this specific expander head, so ensure that it is the correct size prior to beginning.
  4. The number of expansions will be dictated by the tubing size. It is important to make sure the expander head rotates after each expansion to prevent ridges on the inside of the tubing.
  5. Once the tubing is expanded, insert the fitting until it hits the shoulder and allow the PEX to contract around the fitting until secure.
  6. After several seconds, the tubing will secure around the fitting and your connection is made and ready for use.