Learning How to Install PEX Tubing with an Expander – Simpler Than You Think
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.
Table of contents
Measure Your Lengths of PEX Piping…Twice
First, measure and cut the length of PEX you need. That goes without saying. It also goes without saying that you need to account for the wider arcs for anywhere you don’t plan to add a 90-degree elbow or similar bend.
Add the PEX A Expansion Ring
The next step involves placing your expansion ring on the cut end of your PEX. You have several choices when it comes to PEX A expansion sleeves and most perform similarly.
Make the Connection
You can use a manual PEX expansion tool or a cordless tool. We prefer the latter since it greatly simplifies the process and reduces time on the job. In our case, we use the Milwaukee M18 FUEL Pro PEX Expander and also the more compact Milwaukee M12 FUEL Pro PEX Expander.
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.
Start the Process of Expansion
The fourth step has you (in our case) pressing and holding the trigger until the tip of the ring hits the back of the expander cone. Be sure to verify that with each expansion the head shifts position slightly. The tool we use works 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
Once the ring bottoms out, keep the trigger depressed. Count an additional 3-6 expansions. Doing this ensures you have enough time to connect your fitting without it shrinking back to size too quickly.
You also need to hold the PEX tubing and fitting together for a second. The heat from your hand will help shrink the ring and ensure a tight seal. This makes pullback a non-issue.
Final Note About Temperature
The temperature you are working at will also affect the 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.