Unicel C-8412 – 120 sq ft Replacement Pool Filter Cartridge

Product Overview

The Unicel C-8412 is a high-quality OEM replacement cartridge filter designed for larger residential in-ground pool systems. With approximately 120 square feet of pleated media, this cartridge delivers extended filtration and longer run times between cleanings.

Key Features

• ~120 sq ft filtration area for improved debris capture and longer cycles.
• Heavy-duty spun-bonded polyester media with durable molded end caps.
• Open end-cap design (4″ inner diameter) for easy drop-in replacement.
• Compatible with major filter tanks requiring a cartridge of 8-15/16″ diameter × 23-5/16″ length.

Technical Specifications

• Part Number: C-8412
• Filtration Area: ~120 sq ft
• Outside Diameter: ~8-15/16″ (approx. 8.9375″)
• Length: ~23-5/16″
• Pleat Count: ~172 pleats
• End Caps: Open both ends with molded gasket, 4″ I.D.

Applications & Compatibility

This cartridge fits filter vessels that accommodate a 120-sq-ft cartridge and whose dimensions match the specs above (OD ~8-15/16″ × length ~23-5/16″). Confirm your existing cartridge’s size and open end-cap type before purchasing.

Installation Instructions

• Turn off the pump and relieve any system pressure before opening the filter tank.
• Remove the old cartridge and clean out the filter tank, especially the bottom.
• Inspect and ensure the o-ring or tank gasket is in good condition; replace if needed.
• Insert the new C-8412 cartridge, ensuring it seats properly and that the end caps align correctly.
• Reassemble the filter tank, restore system power and monitor pressure and flow after startup.

Troubleshooting

• High pressure soon after installation: Ensure the cartridge fully expanded and there’s no blockage or collapsed pleats.
• Reduced flow or clarity issues: Confirm the cartridge is the correct size, check for damaged media or bypass around end caps.
• Leaks or wet motor compartment: Check tank lid seal and that cartridge doesn’t interfere with the lid or clamp ring seating.

Maintenance Tip

For best results, rinse the cartridge monthly in a moderate debris environment and every 4-6 weeks if heavy use or large debris load. Replace the cartridge when media shows wear, pleats are permanently compressed, or problematic pressure rise persists. Using the correct size filter like the C-8412 helps maintain water clarity and extend your system’s life.