Waterway Plastics OEM 817-4025 spa filter (4CH-926)

Teleweir

Replacement numbers

Unicel 4CH-926, Pleatco PWW25L

Fits Waterway Plastics OEM 817-4025.

Diameter 4-15/16" (125 mm)Length 13-1/2" (343 mm)25 sq ft

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Unicel4CH-926
PleatcoPWW25L (Spec table PDF p.32: PWW25L, 5" x 13-3/16", handle, 1-1/2" female SAE, 25 sq ft, Waterway Teleweir 25. No 817-4025 on that line. Cross-reference PDF p.47: 4CH-926 = PWW25L.)
FilburFC-0168
Topv-groove handle
Bottom2" female SAE
Ø 4-15/16" (125 mm)13-1/2" (343 mm)Side view · end views belowTopBottom
Top: v-groove handle
Bottom: 2" female SAE
Drawn to scale from the listed diameter and length. Handles, threads and closed ends are drawn as symbols, not to scale. 25 sq ft media.

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Waterway Plastics files this cartridge as 4CH-926 cartridge (OEM 817-4025), in the Teleweir group. Numbers on the row: OEM 817-4025; Unicel 4CH-926; Pleatco PWW25L; Filbur FC-0168. 4-15/16" across, 13-1/2" long, top v-groove handle, bottom 2" female SAE, 25 sq ft.

What the sources add about 817-4025: Teleweir 25. Unicel and Waterway's table agree: 4-15/16" x 13-1/2", 25 sq ft, SAE thread. Unicel's spec table says 2" female SAE, 105 pleats, for a 1-1/2" male SAE standpipe (the standpipe note is printed on the 4CH-935 and 4CH-949 spec lines). Pleatco PWW25L is 5" x 13-3/16", 1-1/2" female SAE, 25 sq ft, and that spec line does not print 817-4025. The cross-reference does: 4CH-926 = PWW25L. Filbur FC-0168 is 13-1/16" long and 1-1/2" female SAE. Same length as 817-4050, half the area.

4CH-926 (OEM 817-4025), Pleatco side: Spec table PDF p.32: PWW25L, 5" x 13-3/16", handle, 1-1/2" female SAE, 25 sq ft, Waterway Teleweir 25. No 817-4025 on that line. Cross-reference PDF p.47: 4CH-926 = PWW25L..

817-4025, Filbur note: Dimensional listing: FC-0168, 4-15/16" x 13-1/16", handle, 1-1/2" female SAE, Waterway Teleweir 25, PWW25L, 4CH-926, 25 sq ft. The Waterway manufacturer section does not print 817-4025..

Hold 4CH-926 next to 4CH-949 differs by Unicel 4CH-949, Pleatco PWW50L, Filbur FC-0172, 50 sq ft, OEM 817-4050, note says Teleweir 50. Same 13-1/2" length as 817-4025. Unicel and Waterway's table: 4-15/16" x 13-1/2", 50 sq ft, 2" female SAE, 210 pleats, for a 1-1/2" male SAE standpipe. Pleatco PWW50L is 5" x 13-3/16", 1-1/2" female SAE, 50 sq ft, OEM 817-4050. Filbur FC-0172 matches Unicel's length and 2" female SAE and 50 sq ft, in the Rising Dragon section, and that row does not print 817-4050.; C-4326 differs by Unicel C-4326, Pleatco PRB25-IN, Filbur FC-2375, 13-5/16" long, top 2-1/8" open, bottom 2-1/8" open, OEM 817-2500, note says 25 sq ft open top-load. Unicel: 4-15/16" x 13-5/16", open 2-1/8", 106 pleats, 25 sq ft. Pleatco PRB25-IN lists OEM 817-2500 at 5" outside diameter and the same length. Filbur prints this OEM on two rows: FC-2375 at 13-5/16" (PRB25-IN, C-4326) and FC-2910, which the size table lengths at 13-1/4" and the Waterway section lengths at 12-1/4", with no Pleatco number. The size stored here is Unicel's. The 50 sq ft cartridge of the same length is 817-5000..

Left blank on purpose: Length 13-1/2" (Unicel, Waterway) vs 13-3/16" (Pleatco) vs 13-1/16" (Filbur). Female thread 2" (Unicel) vs 1-1/2" (Pleatco and Filbur). Pleatco's spec line does not print OEM 817-4025..

Pages checked for 817-4025: Unicel 2026 Replacement Guide on 4CH-926 (Waterway list PDF p.64: 817-4025 = 4CH-926, Teleweir, 4-15/16" x 13-1/2", 25 sq ft, 2" female SAE. Spec table PDF p.9: 105 pleats.). Waterway Plastics Service Logic cartridge table on 4CH-926 (Fetched 2026-11-09: 817-4025, 25 sq ft, 4-15/16" x 13-1/2", SAE thread). Pleatco 2023 Catalog on 4CH-926 (Spec table PDF p.32: PWW25L. Cross-reference PDF p.47: 4CH-926 = PWW25L.). Filbur Catalog & Reference Guide on 4CH-926 (Dimensional listing: FC-0168, 4CH-926, PWW25L, 13-1/16" long, 25 sq ft).

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Sources

Not in sources: Length 13-1/2" (Unicel, Waterway) vs 13-3/16" (Pleatco) vs 13-1/16" (Filbur). Female thread 2" (Unicel) vs 1-1/2" (Pleatco and Filbur). Pleatco's spec line does not print OEM 817-4025..