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Freeflow Spas spa filter (5CH-45)
Freeflow Spas
Replacement numbers
Unicel 5CH-45, Pleatco PFF50P4
Fits Freeflow Spas.
Diameter 5-5/16" (135 mm)Length 10" (254 mm)45 sq ft2 models listedSearch this part on Amazon
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| Unicel | 5CH-45 |
|---|---|
| Pleatco | PFF50P4 (Unicel cross-reference PDF p.47: 5CH-45 = PFF50P4. Spec table PDF p.32: 5-5/16" x 10", open 2-1/8", 1-1/2" MPT, 3 oz, 50 sq ft, Freeflow Spas Legend. Application index PDF p.27: Spa Freeflow Legend 50.) |
| Filbur | FC-2401 |
| Top | 2-1/8" (54 mm) / open |
| Bottom | 1-1/2” male thread/MPT |
Bottom: 1-1/2” male thread/MPT
Drawn to scale from the listed diameter and length and open-end sizes. Handles, threads and closed ends are drawn as symbols, not to scale. 45 sq ft media.
Freeflow Spas files this cartridge as 5CH-45 cartridge (Legend), in the Freeflow Spas group. Numbers on the row: Unicel 5CH-45; Pleatco PFF50P4; Filbur FC-2401. 5-5/16" across, 10" long, top 2-1/8" / open, bottom 1-1/2” male thread/MPT, 45 sq ft.
PFF50P4 carries this note from the catalogs: Unicel's spec table prints 5CH-45 for Freeflow Legend: 5-5/16" x 10", open 2-1/8", 1-1/2" MPT, 225 pleats, 3 oz, 45 sq ft. The Freeflow model list puts Legend and Passport on that row. Passport is not in the spec-table model cell, and Filbur and Pleatco do not name Passport. Pleatco PFF50P4 is 50 sq ft. Filbur's size table is 5-5/16" and 45 sq ft with Pleatco cell PFF50P; Filbur's Freedom Spas section prints the diameter as 5-1/4".
5CH-45 (OEM 5CH-45 cartridge (Legend)), Pleatco side: Unicel cross-reference PDF p.47: 5CH-45 = PFF50P4. Spec table PDF p.32: 5-5/16" x 10", open 2-1/8", 1-1/2" MPT, 3 oz, 50 sq ft, Freeflow Spas Legend. Application index PDF p.27: Spa Freeflow Legend 50..
PFF50P4, Filbur note: Dimensional listing PDF p.10: FC-2401, 5-5/16" x 10", open 2-1/8", 1-1/2" MPT, 45 sq ft, PFF50P, 5CH-45. Freedom Spas section PDF p.18 (printed p.35): Legend, 5-1/4" x 10", 45 sq ft, PFF50P..
Freeflow Spas applications recorded for this cartridge: Freeflow Legend, no year range printed, listed by Unicel 2026 Replacement Guide (Unicel spec table. The model list also names Passport on this 5CH-45 row; Passport is not repeated in the spec-table model cell.); Freeflow Legend, no year range printed, listed by Pleatco 2023 Catalog (Pleatco PFF50P4 at 50 sq ft. Filbur FC-2401 at 45 sq ft. Neither names Passport.).
Before ordering 5CH-45, compare it with 4CH-22 differs by Unicel 4CH-22, Pleatco PFF25W-P4, Filbur FC-2399, 4-15/16" diameter, 6-5/8" long, 25 sq ft, note says Unicel's spec table and Freeflow model list assign the open-top 4CH-22 to TLX and RLX: 4-15/16" x 6-5/8", 212 pleats, 3 oz, 25 sq ft, 1-1/2" MPT. Filbur's size table and its Freedom Spas section assign that same open 4CH-22 / FC-2399 to CLX (and FF-150) and print Pleatco PFF25P4. Pleatco's own Unicel cross-reference prints 4CH-22 = PFF25W-P4, which Pleatco sizes at 5" x 6-5/8" for Lagas and does not name TLX, RLX or CLX. The dimension on this row is Unicel's.; and 4CH-23 differs by Unicel 4CH-23, Pleatco PFF25TC-P4, Filbur FC-2400, 4-15/16" diameter, 6-5/8" long, top closed, 25 sq ft, note says Unicel's spec table assigns the closed-top 4CH-23 to Freeflow CLX: 4-15/16" x 6-5/8", 212 pleats, 3 oz, 25 sq ft, 1-1/2" MPT. The Freeflow model list agrees. Filbur and Pleatco agree that 4CH-23 / FC-2400 / PFF25TC-P4 is the closed cartridge, and they assign it to TLX and RLX instead of CLX. Pleatco also names Lagas, FF-100 and Claro. Pleatco's outside diameter is 4-5/8"..
Left blank on purpose: Area 45 sq ft (Unicel, Filbur) vs 50 sq ft (Pleatco). Filbur diameter 5-5/16" in the size table vs 5-1/4" in the Freedom section. Passport is Unicel's model list only. Pleatco number PFF50P4 on the cross-reference vs PFF50P in Filbur's cell..
Source locations for this Freeflow Spas row: Unicel 2026 Replacement Guide on 5CH-45 (Freeflow model list, PDF p.35 (printed p.31): Legend and Passport = 5CH-45, 45 sq ft; spec table PDF p.11 (printed p.7): 225 pleats, model cell Legend, 5-5/16" x 10", open 2-1/8"). Pleatco 2023 Catalog on 5CH-45 (Unicel cross-reference PDF p.47: 5CH-45 = PFF50P4. Spec table PDF p.32: 50 sq ft for Freeflow Spas Legend). Filbur Catalog & Reference Guide on 5CH-45 (Dimensional listing PDF p.10: FC-2401 at 5-5/16" x 10", 45 sq ft. Freedom Spas section PDF p.18 (printed p.35): Legend at 5-1/4" x 10").
Hot tubs listed for this cartridge
The rest of the Freeflow Spas model list is the Freeflow Spas filter by model and year lookup.
| Model / system | Years | Listed by |
|---|---|---|
| Freeflow Legend (Unicel spec table. The model list also names Passport on this 5CH-45 row; Passport is not repeated in the spec-table model cell.) | not given | Unicel 2026 Replacement Guide |
| Freeflow Legend (Pleatco PFF50P4 at 50 sq ft. Filbur FC-2401 at 45 sq ft. Neither names Passport.) | not given | Pleatco 2023 Catalog |
Check the cartridge you removed
Measure diameter, length, and both ends, then compare them with the figures above. The steps are in the measuring guide. Why the bottom decides whether it seals: open-end vs threaded filters. Power, the retainer, and not running the spa empty: how to install a cartridge. Number formats: how Filbur, Unicel and Pleatco numbers compare.
Other Freeflow Spas cartridges
- 4CH-22 cartridge (open top), 4-15/16" (125 mm) × 6-5/8" (168 mm)
- 4CH-23 cartridge (closed top), 4-15/16" (125 mm) × 6-5/8" (168 mm)
All 3 Freeflow Spas spa filters
Every number on this row, on one screen: cross-reference lookup. Published clean and replace intervals for this cartridge, and a buy link for the numbers above: replacement schedule and reorder. The interval comparison by brand: calculator.
Cleaner and test strips
Hose rinse and soak steps are in how to clean a cartridge. Named cleaners and strips are in filter cleaners and test strips.
Filter cleaner and test strips
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Leisure Time O Filter Clean Cartridge Cleaner Listing title: cartridge cleaner, 32 fl oz.
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SpaGuard Filter Cleaner Listing title: filter cleaner for spas and hot tubs, 1 quart.
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AquaChek SPA 6-in-1 Test Strips Listing title: reads total bromine, total chlorine, free chlorine, pH, total alkalinity and total hardness.
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Sources
- Unicel 2026 Replacement Guide: Freeflow model list, PDF p.35 (printed p.31): Legend and Passport = 5CH-45, 45 sq ft; spec table PDF p.11 (printed p.7): 225 pleats, model cell Legend, 5-5/16" x 10", open 2-1/8" (PDF)
- Pleatco 2023 Catalog: Unicel cross-reference PDF p.47: 5CH-45 = PFF50P4. Spec table PDF p.32: 50 sq ft for Freeflow Spas Legend (PDF)
- Filbur Catalog & Reference Guide: Dimensional listing PDF p.10: FC-2401 at 5-5/16" x 10", 45 sq ft. Freedom Spas section PDF p.18 (printed p.35): Legend at 5-1/4" x 10" (PDF)
Not in sources: Area 45 sq ft (Unicel, Filbur) vs 50 sq ft (Pleatco). Filbur diameter 5-5/16" in the size table vs 5-1/4" in the Freedom section. Passport is Unicel's model list only. Pleatco number PFF50P4 on the cross-reference vs PFF50P in Filbur's cell..