How to install PEX tubing - making a crimp connection.


PEX crimp connection tool kit with crimp rings, fittings, and toolsThis tutorial is designed to help you to understand the general techniques used to make a PEX crimp connection.

To make a PEX connection using a crimp method, you will need the following:
  1. PEX tubing;
  2. Brass or poly PEX crimp fitting(s);
  3. PEX crimp ring(s);
  4. PEX tools:

Step 1:

Cut the PEX tubing. To ensure you have a smooth and even cut, position the cutter at 90 degrees to the tubing.
Cutting PEX tubing with a 90-degree straight cut using PEX cutter - side view
Straight cut of PEX tubing for crimp fitting installation - profile view

Step 2:

Slide the PEX crimp ring and over the tubing approximately 2" past the end.

Sliding a PEX crimp ring over the tubing before fitting insertion

Step 3:

Fully insert the PEX fitting into the PEX tubing so that the fitting’s shoulder touches the tubing. Inserting brass PEX fitting fully into PEX tubing before crimping

Step 4:

Position the PEX crimp ring 1/4”-1/8” from the end of the tubing. This way the crimp ring will be right above the PEX fitting’s barbs. Positioning the crimp ring 1/8 to 1/4 inch from tubing end over the fitting barbs

Step 5:

Open the PEX crimp tool’s jaws.

Opening PEX crimp tool jaws before placing over the crimp ring

Step 6:

Position the PEX crimp tool over the crimp ring evenly, at 90-degrees to the tubing. Make sure that jaws of the tool are centered over the crimp ring and it stays in place.
Positioning PEX crimp tool jaws centered over the ring - side view
PEX crimp tool aligned perpendicular to tubing over the crimp ring - profile view

Step 7:

Close the crimp tool’s jaws completely.

Closing crimp tool jaws fully to secure the crimp ring on PEX tubing

Step 8:

Check the connection with a go-no-go gauge. The image below shows a connection which gauges properly. Checking PEX crimp ring with a go-no-go gauge for proper compression
In both examples below, connection was done improperly and must be redone after removing the crimp ring and re-calibrating the tool.
Failed PEX crimp connection that does not pass go-no-go gauge test - example 1
Failed PEX crimp connection that does not pass go-no-go gauge test - example 2

Connection is complete

Properly completed PEX crimp connection after gauge verification

If a connection does not gauge, or it was done improperly, a decrimper tool should be used to remove the crimp ring:

Step 1:

Using PEX cutter, cut off the section of PEX tubing with the fitting. Try to make the cut as close to the end of the fitting as possible without scratching it or damaging the cutter. Cutting off crimped PEX section close to the fitting using a PEX cutter

Step 2:

Open the jaws of the decrimping tool.


Opening jaws of PEX decrimping tool before use

Step 3:

If you’re using an Everhot PXT3101 decrimper, use a quick switch knob to select the PEX tubing size. For the PXT3101 model, the "--" position is for 1/2" PEX, "+-" position if for 3/4" and 1" PEX. Calibrating Everhot PXT3101 PEX decrimper for tubing size using selector knob

Step 4:

Next, visually inspect the PEX decrimping tool. The tool has two jaws – one is for cutting the ring (the sharp one) and one to support the PEX fitting from the inside (the dull one). Inspecting decrimper tool showing sharp cutting jaw and internal support jaw

Step 5:

Insert the decrimping tool into the cut-off section as shown. Positioning decrimper tool jaws around PEX crimp ring and fitting

Step 6:

Close the decrimper’s jaws completely. The ring will split. Closing decrimper tool jaws to cut PEX crimp ring

Step 7:

Rotate the piece 180 degrees and repeat Step 5. The PEX crimp ring will fully split in half, making it easy to remove it by hand.
Deforming and cracking PEX crimp ring with second decrimping cut
Removing split PEX crimp ring from the fitting manually
Removing remaining section of PEX tubing from fitting after decrimping
Removing remaining section of PEX tubing from fitting after decrimping

Step 8:

The remaining piece of PEX tubing can now be easily removed, leaving an undamaged PEX fitting which can be used again. Removing remaining section of PEX tubing from fitting after decrimping

The process of installing PEX tubing installation with a crimp method is the same for both Oxygen Barrier PEX tubing and Non-Barrier PEX types.
PEX crimp connection method described in this tutorial is suitable for all types (A,B,C) of PEX tubing, regardless of brand or color. Typically, both crimp fittings and crimp rings are available in sizes 3/8", 1/2", 5/8", 3/4", 1" and 1-1/4".
Crimp connection method is particularly popular among DIY'ers because of the ability to check a completed connection with a go-no-go gauge. No other connection method gives you such an option.
For sweat or threaded type PEX fittings, the transition part must always be connected first (also cooled off, if it is a sweat connection).
This article is for informative purposes only. For actual installation instructions, refer to manufacturer's manual.

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