Unicel C-9421 Replacement Filter for Jacuzzi CFR-75 (in-line) | 200 Sq. Ft.

Overview

The Unicel C-9421 is a pleated polyester cartridge filter element engineered for in-line commercial and high-capacity residential installations, providing 200 sq ft of filtration area within a single high-pleat-count media pack. Dimensional specifications: 7.0-inch OD, 4.0-inch ID, 31.25-inch length. Construction features Reemay nonwoven polyester media with nominal 20-micron filtration efficiency, supported on an axially rigid PVC core to maintain pleat geometry under sustained ΔP loading. End caps are molded with banded reinforcement at the seating shoulders to ensure positive bypass-free seating in deep-canister housings. The element is rated for continuous service to 104°F and operating pressure to 50 PSI, supporting the heavier-duty in-line filter configurations typical of multi-cartridge commercial manifolds and oversized residential systems sized for reduced service frequency.

Service interval recommendation: pressure-differential-based replacement triggered at ΔP ≥ 8–10 PSI above clean-filter operating baseline, or annually for residential applications. Commercial installations should follow a 30–90 day service cycle keyed to bather load, with documented ΔP logs maintained for jurisdictional compliance. Rinse at 4–6 week intervals or upon initial 8 PSI ΔP rise; chemical soak (TSP or enzyme cleaner) recommended every 3–6 months to remove oils and surfactants resistant to mechanical rinsing. Muriatic acid soak at 1:20 dilution is compatible for calcium scale removal (20 minutes maximum exposure, thorough rinse before reinstallation); enzyme cleaners compatible without restriction. Chlorine tolerance: continuous service at ≤ 10 ppm free available chlorine; bromine compatible at standard sanitization levels. Inspect O-rings and housing seats at each service interval and verify post-installation pressure against documented clean baseline. Standard Unicel 90-day manufacturing defect warranty applies through authorized distribution.

What's Included

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