Saratoga Spas OEM 20245-238 spa filter (4CH-21)

Saratoga Spas

Replacement numbers

Unicel 4CH-21, Pleatco PTL18P4

Fits Saratoga Spas OEM 20245-238.

Diameter 4-5/8" (117 mm)Length 8" (203 mm)19 sq ft

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Unicel4CH-21
PleatcoPTL18P4 (Spec table PDF p.31: PTL18P4, 4-5/8" x 8", 1-1/2" MPT, 18 sq ft, OEM 20245-238 and PVT-25N. Cross-reference PDF p.47: 4CH-21 = PTL18P4.)
FilburFC-0121
Topmolded cone handle
Bottom1-1/2" MPT
Ø 4-5/8" (117 mm)8" (203 mm)Side view · end views belowTopBottom
Top: molded cone handle
Bottom: 1-1/2" MPT
Drawn to scale from the listed diameter and length. Handles, threads and closed ends are drawn as symbols, not to scale. 19 sq ft media.

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Saratoga Spas files this cartridge as 4CH-21 cartridge (OEM 20245-238), in the Saratoga Spas group. Numbers on the row: OEM 20245-238; Unicel 4CH-21; Pleatco PTL18P4; Filbur FC-0121. 4-5/8" across, 8" long, top molded cone handle, bottom 1-1/2" MPT, 19 sq ft.

What the sources add about 20245-238: 1-1/2" MPT, 4-5/8" x 8". Unicel's spec table: 158 pleats, 19 sq ft. The Saratoga line names OEM 20245-238. Pleatco PTL18P4 is the same length and 18 sq ft, and the spec line also names Vita PVT-25N. Filbur FC-0121 agrees with Unicel's 19 sq ft. The 19 stored here is Unicel's and Filbur's figure.

4CH-21 (OEM 20245-238), Pleatco side: Spec table PDF p.31: PTL18P4, 4-5/8" x 8", 1-1/2" MPT, 18 sq ft, OEM 20245-238 and PVT-25N. Cross-reference PDF p.47: 4CH-21 = PTL18P4..

20245-238, Filbur note: Saratoga section PDF p.25: FC-0121, 4-5/8" x 8", 1-1/2" MPT, PTL18-4, 4CH-21, 19 sq ft..

Before ordering 4CH-21, compare it with 4CH-20 differs by Unicel 4CH-20, Pleatco PSG25P4, Filbur FC-0125, 6-3/4" long, 20 sq ft, OEM 20241-238, note says Short Saratoga top-load, 1-1/2" MPT. Unicel's spec table, price index, and Saratoga line all say 4-5/8" x 6-3/4", 204 pleats, 20 sq ft, for OEM 20241-238. That 20 is what is stored. Unicel's Vita line prints the same 4CH-20 as PVT 25 at 25 sq ft. Pleatco PSG25P4 is 4-3/4" x 6-1/2", 25 sq ft, OEM 20241-238. The 2023 Unicel cross-reference has no 4CH-20 line. Filbur's Saratoga section prints FC-0125 at 15 sq ft and names the Pleatco cell PHC25, which Pleatco deactivates with replacement N/A. Filbur's size-table description says 20 sq ft and its column says 25. Filbur's Vita section prints 25 sq ft for OEM PVT-25. The 1-1/4" SAE cartridge of this length is 4CH-920, not this one.; and 4CH-920 differs by Unicel 4CH-920, no Pleatco number, Filbur FC-0124, 6-3/4" long, bottom 1-1/4" SAE, 20 sq ft, no OEM number, note says Same 4-5/8" x 6-3/4" body as 4CH-20, with a 1-1/4" SAE bottom instead of 1-1/2" MPT. Unicel's Saratoga line prints no OEM number. Spec table and price index: 204 pleats, 20 sq ft. Filbur FC-0124 prints 15 sq ft and the Pleatco cell PSG13.5. Pleatco's PSG13.5P4 is 4-3/4" x 5-15/16" and 14 sq ft, OEM 303575, which is not this length and is not on Unicel's Saratoga list, so it is not stored as the equivalent. The 2023 cross-reference has no 4CH-920 line. Filbur's footnote says to remove Saratoga's adapter and match the replacement to the fitting that remains..

Left blank on purpose: Area 19 (Unicel, Filbur) vs 18 (Pleatco). Length agrees at 8"..

Pages checked for 20245-238: Unicel 2026 Replacement Guide on 4CH-21 (Saratoga list PDF p.55: 20245-238 = 4CH-21, 4-5/8" x 8", 19 sq ft. Spec table PDF p.7: 158 pleats, 19 sq ft. Price index PDF p.88: 19 sq ft.). Pleatco 2023 Catalog on 4CH-21 (Spec table PDF p.31: PTL18P4, OEM 20245-238, 18 sq ft. Cross-reference PDF p.47: 4CH-21 = PTL18P4.). Filbur Catalog & Reference Guide on 4CH-21 (Saratoga section PDF p.25: FC-0121, 4CH-21, 19 sq ft).

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Sources

Not in sources: Area 19 (Unicel, Filbur) vs 18 (Pleatco). Length agrees at 8"..