Press Fittings: Large Diameter Installation

Written by Ashley Petersen 2016-11-08

The NIBCO® Press System® 2 ½” – 4” fittings and valves have the same basic design as the ½” – 2” products. However, unlike the ½” – 2” fittings and valves, which are designed to be joined with most pressing tools on the market, NIBCO 2 ½” – 4” fittings and valves can ONLY be installed with NIBCO pressing tools and accessory equipment. This installation video and the following text instructions demonstrate how to install the NIBCO Press System 2 ½” – 4” product.


Before beginning, review the installation instructions found in the NIBCO Press System catalog or the instructions included with the product, and the pressing tool user’s manual, to prevent serious injury.

Step 1: Get Your Equipment ReadyPress Fittings

The equiptment required includes:

  • NIBCO Pressing Tool
  • PC-5 Adapter Jaw
  • NIBCO Pressing Chain (PC-2, PC-3, or PC-4, depending on the size to be crimped)

Step 2: Attach Adapter JawPress Fittings

  • The first step is to remove the battery or unplug the cord on the pressing tool prior to attaching or changing the adapter jaw.

  • Next, push and twist to open the jaw set mounting pin.

  • If the press tool contains a jaw set, slide it out of the crimping tool.

  • Push the silver button on the tool’s red sleeve and slide it toward the handle of the tool as far back as it will go. This red sleeve must be in the back position to be able to crimp the 2 ½”, 3”, and 4” sizes. The rollers on the pressing tool must be in the forward position to allow the red sleeve to return to the forward position.

  • Insert the PC-5 adapter jaw into the pressing tool and push the jaw set mounting pin until it clicks into position.


Step 3: Calibrate the NIBCO Press tool with the NIBCO PC-5 Adapter JawPress Fittings

  • To calibrate the NIBCO pressing tool, insert a fully charged battery into the base of the tool.

  • Complete one tool cycle with the adapter jaw. The tool and jaw are now ready for use.


Step 4: Prepare the Copper TubePress Fittings

  • Common piping practices should be followed when preparing the copper tube. For example: Tubing that is difficult to insert may have burrs or could be out-of-round. Make sure the tubing ends are clean, undamaged and cut square. Deburr the tube’s inside and outside diameter using a half-round file, to prevent damage to the seal.

  • Clean the tube end of all contamination, oils, copper shavings or filings. A smooth transition chamfer is recommended to east the tube insertion past the seal.

  • Emery cloth or sandpaper to clean the tube or remove oxidation IS NOT REQUIRED.


Step 5: Insert the tube into the fitting or valvePress Fittings

  • After preparing the copper tube, the first step is to check the fitting or valve to make sure the EPDM seal is in place and is free of oil and grease.

  • Never lubricate the EPDM seal in the NIBCO® Press System fitting or valve with anything other than water. Oil lubricant, dirt or debris may damage the seal. An improper seal can lead to extensive property damage.

  • Using a tape measure, ruler or insertion depth gauge, mark the tube with a permanent marker to indicate the minimum tube insertion depth. (Refer to the minimum insertion depth table in the instructions for correct depths.)

  • Insert the tube into the fitting or valve using a twisting motion. Make sure the tube is inserted to the proper depth. Failure to do so may result in an improper seal. When inserted properly, the fitting or valve should cover the insertion depth mark.


Step 6: Attach a Pressing Chain to a NIBCO Press System Fitting or ValvePress Fittings

  • Select the correct size pressing chain and pull the pin on the chain which allows the segments to open.

  • Position the chain on the raised bead of the fitting or valve and wrap the chain around the bead with the “pipe side” designation facing the tube.

  • When the chain is fully wrapped around the fitting or valve, reinsert the pin to secure the chain on the assembled joint.

  • If necessary, reposition the fitting on the tube to ensure that the insertion depth mark is covered.


Step 7: Crimp a NIBCO Press Fitting or Valve - 2½"- 4"Press Fittings

  • Once the tubing is inserted into the fitting or valve at the proper depth, squeeze jaw arms to open the adapter jaw. The rollers on the tool must be fully retracted to open the adapter jaw.

  • Place the open adapter jaw into the grooves in the pressing chain and let go of the jaw arms. Make sure the tips of the adapter jaw are completely inserted on each side of the chain.

  • Make sure the tubing is inserted to the proper depth in the fitting or valve, and that everything is aligned properly.

  • With the pressing tool perpendicular to the tube, begin the pressing cycle by pulling the trigger of the pressing tool. (Please note that releasing the trigger will stop the tool once the crimping process has begun. Depressing the trigger again will continue the crimp cycle.)
  • Once the crimp cycle begins and the rollers contact the jaw arms, the tool will complete the crimp cycle, as long as the trigger is depressed.

  • For 2 ½” – 4” joints, the entire cycle duration to make a watertight and permanent connection is approximately 20-30 seconds.

  • After the crimp cycle is complete, press the jaw arms to open and remove the adapter jaw and tool from the pressing chain. Then remove the pressing chain from the fitting or valve. Be sure to avoid any sharp edges that may have formed on the fitting during the crimping operation.


Step 8: Inspect the CrimpPress Fittings

  • Inspect the crimped fitting or valve to ensure a proper crimp and application of the unique NIBCO® Press System witness mark (N). The final crimp should appear pressed uniformly around the fitting or valve.

  • If the witness mark is not evident, inspect the crimped fitting or valve for one of the following:

    • a misaligned tube
    • not fully inserted tube; re-check the depth marks
    • incorrect pressing chain alignment with the fitting contour
  • If one or more of these problems are found, a new section of tubing and a new fitting or valve will need to be prepared, installed, and crimped. PLEASE NOTE that NIBCO Press System 2 ½” – 4” fittings and valves can ONLY be installed with NIBCO pressing tools, NIBCO pressing chains, and the NIBCO adapter jaw.

  • Finally, test the NIBCO Press System in accordance with normal practice and to local jurisdiction piping code.


The NIBCO Press System is a safe, easy and fast way to install a copper piping system, and is backed by a name you can trust. Download your free NIBCO Press Fittings and Valves Quick Reference Guide for more information!

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