The cordless expander is about as easy and foolproof as can be. If you’re wondering how to install PEX tubing with a PEX expander, it’s really pretty straightforward. And if you have access to a cordless model, like the M12 or M18 from Milwaukee, it’ll make your life much easier.
How to Install PEX Tubing with a PEX Expander
First, measure and cut the length of PEX you need. That goes without saying.
Add the Expansion Ring
Second, place your expansion ring on the cut end of your PEX.
Make the Connection
Third, place the fully closed expansion head into the tip of the PEX. If you didn’t already grease the head, be sure to before starting the first connection. That will ensure proper rotation and contraction.
Fourth, press and hold the trigger until the tip of the ring hits the back of the expander cone, being sure to verify that with each expansion the head shifts position slightly. The tool will work pretty quickly.
If you happen to be using a hand pump expander, things will be slower. The mantra to remember is “pump and turn”. You need to keep turning the expander as you go to eliminate potential leaks from a connection that didn’t expand evenly.
Don’t Stop at the End
Last, once the ring bottoms out, keep the trigger depressed and count an additional 3-6 expansions. Doing this will ensure that you have enough time to connect your fitting without it shrinking back to size too quickly.
You also need to hold the PEX and the fitting together for a second. The heat from your hand will help shrink the ring and ensure a tight seal, making pullback a non-issue.
A Note About Temperature
The temperature you are working at will also affect a number of expansions you allow for the PEX at the end of the cycle. As a general guideline, the more head expansions you allow, the better as the temperature warms up. Warmer temps mean the PEX will take back its original shape more quickly. On the flip side, the colder it is, the fewer expansions you want to allow as too many expansions will require you to hold the PEX on your fitting for an extended period of time.