Unicel 4CH-940 Replacement Filter for Dimension One Spas PDO-UF40P2 | 40 Sq. Ft.

Name: Unicel 4CH-940 Replacement Filter for Dimension One Spas PDO-UF40P2 | 40 Sq. Ft.
Brand: Unicel
SKU: UNF4CH940
Price: 43.54 USD
Availability: InStock

$43.54 USD

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Overview

The Unicel 4CH-940 is a pleated polyester spa cartridge filter element providing 40.0 sq ft of filtration area in a compact, high-capacity form factor engineered for premium spa circulation systems. Dimensional specifications: 4.625-inch OD, 2.125-inch ID, 9.25-inch overall length with a closed-bottom, open-top end cap configuration. Construction features Reemay nonwoven polyester media with nominal 15-micron filtration efficiency, ABS injection-molded end caps with UV-stabilized adhesive bond, and a perforated polypropylene core for axial rigidity under spa pump differential loading. Maximum rated continuous service temperature: 115°F, with intermittent excursions to 120°F acceptable per manufacturer test protocol. End cap geometry holds ±0.020-inch OD tolerance for confirmed bypass-free seating in OEM housings.

Spa cartridge service intervals run accelerated relative to pool applications due to higher bather-load-to-water-volume ratios and elevated operating temperatures. Recommended service cycle: fresh-water rinse every 2–4 weeks; chemical soak with dilute TSP or commercial enzyme cleaner every 4–6 weeks to remove body oils, lotions, and surfactant residue that resist standard rinsing. Replace element at ≤ 12-month intervals under typical residential spa duty, or sooner when ΔP rises ≥ 5 PSI above clean-filter operating baseline. Chemical compatibility: polyester media tolerates continuous service at ≤ 10 ppm free available chlorine or ≤ 30 ppm total bromine; muriatic acid wash at 1:20 dilution compatible for calcium scale removal (20-minute maximum exposure, thorough rinse before reinstallation); enzyme cleaners compatible without restriction. ABS end cap adhesive is acid-wash compatible. 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.

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Product Specs

Product SKU	4CH-940
Replaces OEM	PDO-UF40P2
Filter Model	Dimension One Spas PDO-UF40P2
Filtration Area	40
Length	15"
Outer Diameter	4-5/8"
Center Hole	1-1/4" SAE
Media	3 oz
Endcap Material	Durable Polyurethane
Pleat Count	176
Pack Options

Compatibility Table

Brand	Part Number	Type	Status
Unicel	4CH-940	OEM-Compatible	Compatible
Dimension One Spas	PDO-UF40P2	OEM Original	OEM
Pleatco	PDO-UF40P2	Aftermarket	Compatible
Filbur	FC-0177	Aftermarket	Compatible

Unicel 4CH-940 Replacement Filter for Dimension One Spas PDO-UF40P2 | 40 Sq. Ft.

$43.54 USD

Verify Your Fit

How to Measure

Confirm all three dimensions match your existing cartridge before ordering.

Length

15" — top endcap to bottom

Outer Diameter

4-5/8" — widest point across

Center Hole

1-1/4" SAE — inside of the hole

Frequently Asked Questions

Still have questions? Our knowledgeable support agents are standing by to help.

Contact Support

What if it doesn't fit?

We back every order with an exact-fit guarantee. If it doesn't fit your filter housing, contact us within 30 days for a full refund or exchange — no hassle, no restocking fee. Call or text (732) 395-2225.

How long will these last?

With regular cleaning, expect 1–2 seasons of use. Rinse with a garden hose every 4–6 weeks, and do a deep soak in filter cleaner once or twice a season. Replace when you see collapsed pleats, tears in the media, or pressure stays high after a fresh clean.

How do I confirm this fits before I order?

Measure your existing cartridge in three spots: length end-to-end, outer diameter at the widest point, and the inner diameter of the center hole. If all three match the specs listed above, it's a direct fit.