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Pentair Union Nut C-Clip (39104500)

This small but critical component is a snap-on "C-clip" designed to hold the union nut in place on the bulkhead of various Pentair filters and pumps. Without this clip, the union nut would slide down the pipe, making it impossible to create a sealed connection to your equipment.

Key Features

  • Precision Snap-Fit: Engineered with specific tension to "click" into the groove of the bulkhead, ensuring the union nut stays positioned for easy threading.
  • High-Impact Polymer: Constructed from a specialized reinforced plastic that resists chemical degradation from chlorine, acid washes, and UV exposure.
  • Universal Pentair Fit: While tiny, it is the standard retainer for the most popular filtration lines, including Clean & Clear, Predator, and Warrior series.
  • Zero-Tool Install: Designed to be spread slightly by hand and snapped onto the pipe groove, requiring no pliers or specialized equipment.

Specifications

Pentair Union Nut C-Clip / Ring Retainer (39104500)

A small but critical snap-on "C-clip" precision-engineered to secure the union nut on various Pentair filtration and pump systems. This retainer holds the nut in place on the bulkhead; without it, the nut would slide down the pipe, making it impossible to create a sealed, leak-proof connection.

Technical Specification Sheet
Part Number39104500 (39104500Z)
UPC788379699475
MaterialHigh-Density Black ABS Polymer
Inner DiameterApprox. 2.9" (for 2" Plumbing)
DimensionsApprox. 3" x 3" x 0.12"
System Compatibility
Cartridge FiltersClean & Clear�, Plus, Predator�
D.E. FiltersWarrior�, EasyClean�
Specific ModelsCC75, CC100, CC125, CC150
Pump SeriesMaxim� & Standard Unions
Paired PartsNut (271096), O-ring (19237)
Deep-Dive Key Features
Precision Snap-Fit: Engineered with specific tension to "click" into the groove of the bulkhead, preventing union nut movement.
High-Impact Build: Constructed from reinforced plastic that resists chemicals (chlorine/acid) and UV exposure.
Zero-Tool Install: Designed to be spread slightly by hand and snapped onto the pipe groove without specialized equipment.
System Integrity: Essential for maintaining proper operational pressure and leak-proof plumbing seals.

?? Critical Pressure & Safety Warnings

PRESSURE HAZARD: Never attempt to remove or adjust the C-clip while the pump is running. If the clip fails under pressure, the pipe can blow off with enough force to cause severe injury.
THE 0-PSI RULE: Before servicing, turn off the pump and open the Manual Air Relief Valve. Wait until the gauge reads exactly 0 PSI before touching the union or retainer.
NO LUBE ON CLIP: Lubricating the retainer clip with silicone or grease can cause it to slide out of its groove unexpectedly. Only lubricate the union O-rings.
?? Expert Knowledge & Installation Tips
  • The "Click" Test: You must hear a distinct "snap" during install. If it feels loose, the bulkhead groove may be worn, which leads to "nut-slip" and leaks.
  • Orientation Matters: Ensure the flat side of the clip faces the union nut to distribute pressure evenly and prevent the plastic from cracking.
  • Temperature Sensitivity: In freezing climates, these clips become brittle. If reassembling in spring, soak the clip in warm water for a minute to restore flexibility.
  • The "Penny" Trick: If the clip is stuck, use a stiff coin or plastic putty knife to pry it. Avoid metal screwdrivers which can gouge the bulkhead.
PROCEED WITH CAUTION: This is a small part but vital for safety. Always turn off power to the pump before attempting any equipment pad maintenance.
CHOKING HAZARD: This is a small component; keep it away from children and pets.
GENERAL DISCLAIMER: This is a genuine Pentair OEM replacement part. Always verify that your filter or pump model uses 2" plumbing bulkheads before purchasing to ensure fitment.
39104500

Pentair Union Nut C-Clip (39104500)

$5.10
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Pentair

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