Product Overview

The Pentair 261055 2" Side Mount Multiport Valve is a genuine Pentair replacement valve designed for compatible Triton® sand filters and Quad D.E.® filters. It provides convenient control of filtration, backwashing, rinsing, waste and other filter functions through an easy-to-operate multi-position handle.

Pentair identifies 261055 as the SM 20-3 2-inch multiport valve with a 7-1/2-inch centerline. It is a direct choice for compatible Pentair side-mount filtration systems requiring this specific flow configuration.

Key Features

• Genuine Pentair OEM replacement valve
• Manufacturer Part Number: 261055
• 2-inch plumbing connections
• Side-mount multiport design
• 7-1/2" centerline
• Pentair designation: SM 20-3
• Designed for compatible Triton sand filters
• Compatible with applicable Quad D.E. filters
• Durable PVC valve body
• Six-position positive-lock operation
• Dedicated winterizing position
• Convenient single-handle operation
• Ideal for replacement or new filter installations

Pentair's side-mount valves feature a PVC body, six-position positive-lock operation and a special winterizing position.

Specifications

Compatible Filter Families

Pentair lists the 261055 for compatible:

• Pentair Triton® II Sand Filters
• Pentair Triton side-mount sand filter configurations
• Pentair Quad D.E.® Filters

It is specifically listed among the current Triton II valve options as the 2" MPV for sand filters (SM 20-3).

Important Compatibility Note

Do not select a multiport valve based only on the pipe diameter.

Pentair manufactures several visually similar valves with different internal flow patterns. For example, 261152 is intended for FNS/FNS Plus/NSP applications, while 261055 is designed around the Triton and Quad D.E. flow configuration. Verify the existing valve part number, filter model and port orientation before ordering.

Multiport Valve Functions

Depending on the filtration system and installation, the multiport valve provides the common operating positions needed for maintaining a pool filtration system, including:

Filter – Normal pool filtration operation.

Backwash – Reverses water flow through the filter to remove accumulated debris.

Rinse – Resettles the filter media and helps clear the plumbing following backwashing.

Waste – Sends water directly to the waste line rather than returning it to the pool.

Closed – Stops flow through the valve for applicable servicing procedures.

Recirculate – Bypasses the filter while allowing water to continue circulating through the pool system.

Always shut the pump off before changing valve positions.

Why Replace a Multiport Valve?

A worn or damaged valve can lead to several filtration problems, including:

• Water leaking from the waste line
• Water leaking around the valve
• Difficult or stiff handle operation
• Internal water bypass
• Reduced filtration performance
• Cracked valve body
• Damaged spider gasket or diverter
• Incorrect flow between filter ports

Replacing the complete valve can be an effective solution when several internal components are worn or the valve housing itself has been damaged.

Installation Information

The 261055 uses a 7-1/2-inch centerline, making proper alignment with the filter inlet and outlet connections important.

Before installation:

1. Turn off power to the circulation pump.
2. Completely relieve filter pressure.
3. Verify the replacement valve part number.
4. Confirm the 2" plumbing configuration.
5. Check the filter inlet and outlet flow orientation.
6. Properly support the plumbing so its weight does not place stress on the valve.
7. Inspect all seals and O-rings before restarting the system.

Pentair specifically recommends supporting connected plumbing and using only suitable PTFE- or silicone-based lubricants on compatible O-rings and seals.

Frequently Asked Questions

What is Pentair 261055?

261055 is Pentair's 2" side-mount multiport valve, SM 20-3, with a 7-1/2" centerline for compatible Triton and Quad D.E. filters.

Does 261055 fit Pentair Triton II sand filters?

Yes. Pentair lists 261055 as one of the valve options for the Triton II side-mount filter family.

Does it also fit Quad D.E. filters?

Yes. Pentair specifically lists the 261055 for compatible Triton and Quad D.E. filters.

What size is the valve?

It uses 2-inch plumbing connections.

What is the centerline measurement?

The valve has a 7-1/2-inch centerline.

Is this the SM 20-3 valve?

Yes. Pentair 261055 is the SM 20-3 configuration.

Is 261055 the same as 261152?

No. They are different flow configurations. 261055 is intended for Triton/Quad D.E. applications, while 261152 is listed for FNS, FNS Plus and NSP filters.

Should the pump be running when changing valve positions?

No. Always turn the pump off before moving the multiport valve handle.