Unicel C-6900-4 Filter Cartridge 25 Sq Ft 4-pack

Product Description

The UNICEL C-6900-4 is a replacement filter cartridge designed for pool filtration systems requiring a 25 square foot filter element. Sold as a 4-pack, each cartridge measures 6.25 inches in diameter and 32.75 inches in length, with open end caps featuring molded gaskets on both the top and bottom at a 3-inch inner diameter. The filter media is 8-ounce DE-grade material with a 42-pleat configuration, delivering efficient particulate removal and longer intervals between cleaning cycles. This cartridge is installed by pool service professionals and knowledgeable DIYers performing routine filter maintenance.

This cartridge set is suited for residential and light commercial pool filtration applications using Quad DE-style filter housings rated for 100 square feet of total filter area. A full filter replacement requires four individual 25 square foot cartridges, making this 4-pack a complete replacement kit for a single filter vessel. The cartridge meets OEM specifications and is a direct-fit replacement for Pentair Pool Products part number 178656.

Key Features

• 25 square feet of filter area per cartridge, 100 square feet total for a full 4-cartridge set
• 8-ounce DE filter media with 42-pleat design for efficient filtration
• Open end caps with molded gaskets on both ends for secure seating and leak-free operation
• 3-inch inner diameter on both top and bottom end caps
• Longer service intervals between cleanings compared to standard media
• Meets OEM specifications for direct-fit replacement

Compatibility

Direct replacement for Pentair Pool Products part number 178656. Four 25 square foot cartridges are required per filter vessel for a complete replacement.

Installation Notes

Installation is performed by pool service technicians during scheduled filter maintenance. Before opening the filter housing, shut off the circulation pump and relieve all system pressure through the air relief valve. Inspect O-rings and housing seals during cartridge replacement and replace any components showing wear. Follow local pool equipment codes and the filter manufacturer's assembly instructions when reinstalling the end cap assembly and closure band.