Waterway Plastics OEM 817-1000 spa filter (C-4995)

Top load, the C-4970 replacement

Replacement numbers

Unicel C-4995, Pleatco PCAL100

Fits Waterway Plastics OEM 817-1000.

Diameter 4-15/16" (125 mm)Length 23-5/8" (600 mm)95 sq ft

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UnicelC-4995
PleatcoPCAL100 (Spec table PDF p.32: PCAL100, 5" x 23-5/8", open 2-1/8", 100 sq ft, OEM 817-1000. Cross-reference PDF p.47: C-4995 = PCAL100. Deactivated PCAL75 points here.)
FilburFC-2940
Top2-1/8" (54 mm) open
Bottom2-1/8" (54 mm) open
Ø 4-15/16" (125 mm)23-5/8" (600 mm)Side view · end views belowTopBottom
Top: 2-1/8" (54 mm) open
Bottom: 2-1/8" (54 mm) open
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. 95 sq ft media.

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Waterway Plastics files this cartridge as C-4995 cartridge (OEM 817-1000), in the Top load, the C-4970 replacement group. Numbers on the row: OEM 817-1000; Unicel C-4995; Pleatco PCAL100; Filbur FC-2940. 4-15/16" across, 23-5/8" long, top 2-1/8" open, bottom 2-1/8" open, 95 sq ft.

What the sources add about 817-1000: The cartridge Unicel names in place of discontinued C-4970. Unicel's spec table and Waterway OEM line: 4-15/16" x 23-5/8", open 2-1/8", 222 pleats, 95 sq ft. That 95 is what is stored. Waterway's own table calls 817-1000 a 100 sq ft in-line cartridge. Pleatco PCAL100 is 5" x 23-5/8", 100 sq ft, OEM 817-1000. Filbur's Waterway section prints FC-2940 at 100 sq ft, and another FC-2940 row prints 95. Same length as the 75 sq ft cartridge it replaces.

C-4995 (OEM 817-1000), Pleatco side: Spec table PDF p.32: PCAL100, 5" x 23-5/8", open 2-1/8", 100 sq ft, OEM 817-1000. Cross-reference PDF p.47: C-4995 = PCAL100. Deactivated PCAL75 points here..

817-1000, Filbur note: Waterway section PDF p.28: FC-2940, OEM 817-1000, PCAL100, C-4995, sq ft column 100. A later size-table row prints FC-2940 / C-4995 at 95..

Hold C-4995 next to C-4970 differs by Unicel C-4970, no Pleatco number, Filbur FC-2930, 75 sq ft, OEM 817-7500, note says 75 sq ft top-load. Unicel's Waterway line prints 817-7500 = C-4970 at 75 sq ft and says C-4970 is discontinued: use C-4995. C-4995 is 817-1000, which Unicel rates at 95 sq ft, so the named replacement is not a 75. Waterway's current table still lists 817-7500 at 75 sq ft. Filbur FC-2930 still prints C-4970, PCAL75, and 817-7500 at 75 sq ft. Pleatco's deactivated list sends PCAL75 to PCAL100 and does not print 817-7500. PCAL100 is not stored here; it is the equivalent on the 817-1000 row.; 4CH-926 differs by Unicel 4CH-926, Pleatco PWW25L, Filbur FC-0168, 13-1/2" long, top v-groove handle, bottom 2" female SAE, 25 sq ft, OEM 817-4025, note says 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..

Left blank on purpose: Area 95 (Unicel spec and Unicel Waterway line) vs 100 (Waterway's table, Pleatco, Filbur Waterway section). A second Filbur row prints 95. Outside diameter 4-15/16" vs Pleatco 5"..

Pages checked for 817-1000: Unicel 2026 Replacement Guide on C-4995 (Waterway list PDF p.64: 817-1000 = C-4995, 95 sq ft, and the C-4970 note that says to use it. Spec table PDF p.9: 222 pleats, 95 sq ft.). Waterway Plastics Service Logic cartridge table on C-4995 (Fetched 2026-11-09: 817-1000, 100 sq ft, in-line top mount). Pleatco 2023 Catalog on C-4995 (Spec table PDF p.32: PCAL100, 100 sq ft, OEM 817-1000. Cross-reference PDF p.47: C-4995 = PCAL100.). Filbur Catalog & Reference Guide on C-4995 (Waterway section PDF p.28: FC-2940 at 100 sq ft. Another FC-2940 row prints 95 sq ft.).

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Sources

Not in sources: Area 95 (Unicel spec and Unicel Waterway line) vs 100 (Waterway's table, Pleatco, Filbur Waterway section). A second Filbur row prints 95. Outside diameter 4-15/16" vs Pleatco 5"..