Unicel C-9999 Replacement Filter for Waterway 817-0250P | 100 Sq. Ft.

Overview

The Unicel C-9999 is a high-capacity pleated polyester cartridge filter element engineered for large-volume spa and small commercial circulation systems, delivering 100 sq ft of effective filtration area through a Reemay nonwoven polyester media pack with nominal 15-micron filtration efficiency. The element is constructed with ABS injection-molded end caps in a closed-bottom, open-top configuration, providing axial structural integrity under sustained operating pressure and dimensional stability at elevated water temperature. Media bonding to end caps is achieved with chemically resistant urethane adhesive rated for continuous service at standard spa water chemistry. Maximum rated temperature is 104°F for continuous service with intermittent excursions tolerated to 120°F under manufacturer testing protocol. The element's high pleat count and 100 sq ft filtration area extend service intervals and reduce ΔP rise rate relative to lower-capacity equivalents in equivalent bather-load applications.

Service interval recommendation for spa and light commercial applications: rinse with fresh water every 2–4 weeks; chemical soak in dilute TSP or enzyme cleaner every 4–6 weeks to remove accumulated oils, lotions, and surfactants that resist mechanical rinsing. Replacement is triggered at ΔP ≥ 5–8 PSI above clean-filter operating baseline, or on a 12-month calendar cycle for continuous-duty installations, whichever occurs first. Chemical compatibility: polyester media tolerates continuous service at ≤ 10 ppm free available chlorine or ≤ 30 ppm total bromine. Muriatic acid wash at 1:20 dilution is compatible with the ABS end cap construction for removal of calcium scale; limit exposure to 20 minutes maximum and rinse thoroughly prior to reinstallation. Enzyme cleaners compatible without restriction. Standard Unicel 90-day manufacturing defect warranty applies through authorized distribution channels.

What's Included

Your order includes the selected quantity of replacement pool filter cartridges. Each unit is individually inspected for quality before shipping.