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Pentair FNS® PLUS Fiberglass D.E. Filter
The filter that delivers crystal clarity.
Filtering with diatomaceous earth (D.E.) provides exceptionally clear water. D.E. filters remove the smallest contaminants, down to 5 microns, which is significantly finer than a grain of sand (1,000 microns). The D.E. material coats the filter grids, forming a porous layer that captures microscopic impurities like dirt, algae, and bacteria while allowing water to pass through.
FNS PLUS FIBERGLASS D.E. FILTER
The culmination of 40 years of pool filter experience.
Pentair FNS Plus filters feature curved grids designed to maximize filtration area and minimize flow restrictions, leading to lower pumping power requirements and reduced utility costs. These filters are engineered for superior water clarity, easy maintenance, and long-term reliability.
KEY FEATURES
Durability
The tank is constructed from chemical-resistant, fiberglass-reinforced polypropylene, ensuring exceptional strength and longevity.
Simplify maintenance
An easily removable filter grid pack simplifies maintenance procedures and saves time.
Convenience
A conveniently located 1/2" drain facilitates easier and more efficient cleanout and 100% draining.
Maintain efficiency
The High Flow™ Manual Air Relief Valve, combined with continuous internal air relief, works together to maintain efficient filtration and help prevent overpressurization.
How a D.E. Filter Works
When D.E. is introduced into the filter system, it coats the filter cloth. As water passes over the filter grids, the D.E. particles capture even the smallest suspended dirt particles. When cleaning is needed, the water flow is simply reversed.
Versatile upgrade for fiber-optic lighting
Features 2" plumbing connections for maximum flow, suitable for fiber-optic lighting installations.
Specifications and Performance
Model Number
Filter Area Sq. Ft.
Vertical Clearance*
Filter Diameter
Flow Rate GPM** Comm.***
Turnover Capacity (Gallons)
8 hrs.
10 hrs.
12 hrs.
FNSP 24
24
48"
21.5"
48
23,040
28,800
34,560
FNSP 36
36
62"
21.5"
72
34,560
43,200
51,840
FNSP 48
48
74"
21.5"
96
46,080
57,600
69,120
FNSP 60
60
86"
21.5"
120
57,600
72,000
86,400
*Required clearance to remove filter elements.
**Flow rate is based on 2.0 GPM per square feet of filter area. Actual system flow will depend on plumbing size and other system components.
***Maximum flow rate.
Pentair TradeGrade
The TradeGrade family of products is exclusively made for and sold by the world's most demanding pool professionals.
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