EZ-FLO Steel Injection Barbs

Follow these steps when building a custom coupler or replacing barbs in an existing one.

Step 1: Select the Correct Size
Choose the Small barb (IEZVFS) for installation into 3/4" through 1-1/2" PVC pipe or fittings. Choose the Medium barb (IEZVFM) for 2" PVC pipe. Using the wrong size will result in a poor fit and may prevent the venturi from functioning correctly.

Step 2: Drill the Pilot Hole
Using a 5/16" drill bit designed for plastic (not a standard wood bit, which can shatter PVC), drill through the wall of your PVC pipe or fitting at the injection point. Drill two holes — one for the inlet barb and one for the outlet barb — spaced according to your coupler design.

Step 3: Tap the Threads
Use a 1/8 NPT tap to cut threads into each drilled hole. Apply thread lubricant if needed, and tap carefully to avoid cracking the PVC.

Step 4: Orient and Install the Barbs
This step is critical. The tapered ends of each barb must face outward, away from the pipe interior. Look for the molded circle imprint on the beveled side — this side faces outward. Incorrect orientation will prevent water from flowing into and out of the injection port, and the EZ-FLO injector will not function. Thread each barb firmly into the tapped hole.

Step 5: Connect the EZ-FLO Tank Tubing
Once both barbs are installed, connect the 1/4" tubing from your EZ-FLO fertilizer tank to the barb fittings. Turn on the irrigation system and verify the injector is drawing fertilizer from the tank into the line.

What is the difference between the Small and Medium barbs?
The Small barb (IEZVFS, part # K-RI8V-S) is designed for use with 3/4" through 1-1/2" PVC pipe, while the Medium barb (IEZVFM, part # K-RI8V-M) is designed for 2" PVC pipe.

My EZ-FLO injector is not dispensing fertilizer after I installed the barbs — what went wrong?
The most common cause is reversed barb orientation. The tapered ends must face outward; if they are installed facing inward, water cannot flow through the venturi ports and no fertilizer will be drawn into the line.

Can I use these barbs to build a coupler in a PVC fitting instead of directly in the pipe?
Yes. You can drill and tap the barbs into a compatible PVC union or coupling fitting as an alternative to drilling directly into the mainline pipe.

Can I use a standard wood drill bit to drill the hole for these barbs?
No. You must use a drill bit specifically designed for plastic. Standard wood bits can shatter PVC pipe, ruining the fitting and potentially causing injury.

Do these barbs work with both the EZ-FLO Hose Thread units and the High-Pressure mainline units?
These steel venturi fittings are specifically designed for use with EZ-FLO mainline installation couplers that are drilled and tapped into PVC pipe — they are not used with hose thread (faucet bib) units, which have a different connection system.