Product Overview

The Pentair 59023400 Grid Assembly is a genuine replacement complete D.E. grid assembly designed for the Pentair FNS Plus 48 sq. ft. D.E. filter. This pre-assembled internal grid cluster replaces the filter’s worn, torn, cracked, or damaged internal element assembly to help restore proper D.E. filtration performance.

This assembly is designed as a direct replacement for compatible 48 sq. ft. vertical-grid D.E. filters and includes the major internal grid components needed for a complete element cluster replacement.

Ideal For

Pentair FNS Plus 48 sq. ft. D.E. filter repairs
Replacing worn or torn D.E. grids
Replacing a damaged internal grid cluster
Restoring filter efficiency and water clarity
Pool service technicians
Residential pool filter maintenance
D.E. filter rebuilds

Key Features

Genuine Pentair replacement grid assembly
Designed for FNS Plus 48 sq. ft. D.E. filters
Complete pre-assembled internal element cluster
Includes eight 24-inch grids
Includes top manifold, bottom manifold, and tie rods
Drop-in design helps simplify filter rebuilds
Restores proper D.E. filtration performance
Ideal replacement when multiple grids or manifolds are damaged
Designed for compatible Pentair, PacFab, and select American Products 48 sq. ft. D.E. filters

Benefits

The Pentair 59023400 complete grid assembly helps restore filtration performance by replacing the internal D.E. grid cluster inside a compatible FNS Plus 48 filter. Over time, D.E. grids can tear, crack, warp, collapse, or become clogged with scale and oils that no longer clean out properly.

Replacing the complete assembly can improve water clarity, filter efficiency, and system performance. Because this assembly is pre-assembled, it helps save time compared to rebuilding the filter with individual grids, manifolds, and tie rods separately.

Specifications

Customer-Facing Q&A

What does the Pentair 59023400 replace?
The Pentair 59023400 replaces the complete internal D.E. grid assembly on compatible FNS Plus 48 sq. ft. D.E. filters.

Does this include all the grids?
Yes. This assembly includes eight 24-inch D.E. grids.

Is this already assembled?
Yes. This is commonly sold as a pre-assembled complete grid assembly, making it easier to install compared to replacing each grid individually.

Which filter does this fit?
This part is designed for the Pentair FNS Plus 48 sq. ft. D.E. filter, commonly listed as model FNSP48 and filter model 180008.

Does this include the filter tank?
No. This is only the internal grid assembly. It does not include the filter tank, clamp, lid, valve, air relief assembly, plumbing, or D.E. powder.

Will this fit the FNS Plus 60 filter?
No. The FNS Plus 60 uses a different grid assembly. This part is for the 48 sq. ft. model only.

When should I replace the full grid assembly?
Replace the full assembly if multiple grids are torn, cracked, warped, heavily scaled, collapsed, or if the manifold or tie rods are damaged.

Confirm Before Ordering

Confirm your filter model and square footage before ordering. This assembly is for the FNS Plus 48 sq. ft. D.E. filter and uses 24-inch grids. It is not for FNS Plus 24, 36, or 60 sq. ft. models.

Always relieve system pressure, shut off equipment, and follow the filter manufacturer’s service instructions before opening any pressurized filter tank.