AquaMatic K520-RFN Internal Parts Kit (Plastic) for Normally Open Valves

Restore the sealing performance and hydraulic control of your water treatment system with the Genuine AquaMatic K520-RFN Internal Parts Kit (SKU: 1079600). This comprehensive plastic internal rebuild kit is manufactured by AqMatic (formerly Pentair) specifically for the 1/2-Inch K520 Series Composite Body Diaphragm Valves.

Engineered from corrosion-resistant, high-grade thermoplastics (such as Noryl/PVC), this kit replaces worn-out components inside Normally Open (NO) valve configurations. It protects your system against internal bypass leaks, loss of pressure control, and premature valve failure in demanding commercial or industrial setups.

Key Features & Benefits

• Premium Composite Construction: Built from rugged, glass-filled thermoplastics designed to handle deionized water, acids, caustic chemicals, and harsh fluids without degrading.

• Optimized for Normally Open (NO) Valves: Tailored precisely to fit standard 1/2" K520 configurations, ensuring identical factory-spec stroke length and closing tolerances.

• Cost-Effective In-Line Rebuild: True to AquaMatic’s signature design, these parts can be dropped in while the valve remains in-line—saving you from costly piping disassemblies and extensive system downtime.

• Maintains Low Pressure Drop: Brand new internal alignment components ensure the valve retains its high-flow, low-pressure loss Y-pattern performance.

Comprehensive Kit Parts List

The K520-RFN Internal Parts Kit replaces the primary moving and sealing internals within the valve body. Depending on the exact historical schematic version, this plastic kit typically consists of the following foundational items:

• Disc Screw: Item No. 2
• Shaft: Item No. 4
• Shaft Guide: Item No. 5
• Lower Diaphragm Plate: Item No. 10
• Upper Diaphragm Plate: Item No. 11
• Screw: Item No. 16

Technical Specifications

Professional Installation Advice

To complete an internal component swap seamlessly, it is highly recommended to use the specialized AquaMatic 520-Z Assembly Tool. The tool hooks perfectly into the plastic shaft guide slots, protecting the new composite threads from stripping or fracturing during reassembly.

Pro Maintenance Checklist: While the valve cap is off to install the K520-RFN internal parts, it is the perfect window to check your main diaphragm. Consider pairing this kit with a K520-RA (EPDM), K520-RAJ (Butyl), or K520-RAV (Viton) Seal & Diaphragm Kit for a complete factory-fresh overhaul.