Pentair 178581 Clean & Clear 420 Sq Ft Filter Lid Assembly

What This Part Is Used For
Pentair 178581 Lid Assembly - Clean/Clr, 420Sqft, FNS Plus is a replacement lid for compatible FNS Plus 420Sqft filters. It seals the large cartridge filter housing.

Why This Part Matters
A damaged lid can compromise pressure and lead to water loss. Proper sealing ensures consistent filtration and system efficiency. Replacing a cracked lid prevents air intrusion and leaks.

Key Features and Specifications

• Pentair manufacturer part number 178581
• For FNS Plus 420Sqft filter
• Clean/Clr configuration
• Filter lid assembly
• OEM Pentair part

Installation and Fitment Guidance
Turn off pump and relieve system pressure before removal. Inspect and replace O-ring if needed during installation. Confirm by manufacturer part number before ordering.

About the Pentair Brand
Pentair manufactures high capacity cartridge filters for residential applications. Their FNS Plus series is widely installed in the field. Using genuine Pentair lids ensures correct sealing and performance. Technicians rely on Pentair for trusted filtration components.

Common Service Context
This lid is typically replaced during major filter maintenance when structural cracks develop from age or pressure cycling.