Product Overview
The Pentair 170016 FNS Plus Tank Bottom Assembly is a genuine OEM replacement lower tank body for the Pentair FNS Plus 36 sq ft D.E. filter. This assembly forms the bottom half of the filter tank and supports the internal standpipe, grid assembly, bulkhead fittings, and sealing surface needed for proper filter operation.

This replacement part is commonly used when the original tank bottom is cracked, leaking, damaged, or no longer sealing properly at the clamp band connection.

Ideal For
Replacing the lower tank body on a Pentair FNS Plus 36 sq ft D.E. filter model FNSP36.

Key Features

• Genuine Pentair OEM replacement part
• Designed for Pentair FNS Plus 36 sq ft D.E. filters
• Replaces the lower tank body assembly
• Helps restore proper filter housing integrity
• Supports the internal standpipe and D.E. grid assembly
• Provides the lower sealing surface for the tank O-ring and clamp band
• Durable molded construction for pool filtration use
• Used for cracked, leaking, or damaged tank bottom repairs
• Helps avoid replacing the complete filter when only the lower tank is damaged

Benefits
The Pentair 170016 tank bottom assembly helps restore the structural base of the FNS Plus filter. A damaged or cracked tank bottom can cause leaks, pressure issues, or unsafe filter operation. Replacing the lower tank assembly with the correct OEM part helps maintain proper filtration performance and keeps the filter housing matched to the original factory design.

This is a practical repair option when the upper tank, clamp, grids, and other components are still serviceable.

Compatibility
Designed for the Pentair FNS Plus 36 sq ft D.E. filter, commonly identified as model FNSP36.

Always confirm your filter model number, tank size, clamp style, and parts diagram before ordering. Some older FNS Plus filter configurations may require additional parts depending on the existing clamp band and internal components.

Specifications

Important Installation Note
Before replacing the tank bottom assembly, fully shut down the pool system, release all filter pressure, and confirm the filter is completely depressurized. Inspect the tank O-ring, clamp band, bulkhead fittings, standpipe, grids, manifold, air relief assembly, and drain components during replacement.

For older FNS Plus filters, confirm whether your existing clamp band is compatible with the replacement tank bottom before ordering.

Customer-Facing Q&A

Q: What is Pentair part 170016 used for?
A: It replaces the lower tank body assembly on the Pentair FNS Plus 36 sq ft D.E. filter.

Q: Which filter does this fit?
A: It is designed for the Pentair FNS Plus 36 sq ft D.E. filter, model FNSP36.

Q: Does this include the standpipe?
A: Yes. This tank bottom assembly is commonly listed with the standpipe included.

Q: Is this the complete filter?
A: No. This is the bottom tank assembly only. It does not include the upper tank, clamp band, complete grid set, manifold, or full filter assembly unless otherwise stated.

Q: Can this fix a cracked lower filter tank?
A: Yes, if the damage is limited to the lower tank section and the rest of the filter is still in good condition.

Q: Should the tank O-ring be replaced at the same time?
A: It is recommended to inspect and replace worn O-rings, seals, and related hardware during tank service to help prevent leaks.

Q: Is professional installation recommended?
A: Yes. D.E. filters operate under pressure, so professional installation is recommended for safety and proper fitment.