Product Overview

The Hayward ProSeries 31" Sand Filter Top Mount W3S310T2 is a high-capacity sand filtration system designed for dependable pool water clarity, strong flow performance, and simple maintenance. Built with a rugged, corrosion-proof polymeric tank and an included 2" top-mount VariFlo multiport valve, this filter is ideal for larger residential pool systems that require reliable filtration and efficient operation.

Its large tank and 500 lb sand capacity provide a deep sand bed for trapping dirt, debris, and fine particles. The top-mount valve design makes everyday operation easy, while the internal diffuser and self-cleaning lateral system help distribute water evenly for balanced filtration and effective backwashing.

Ideal For

Larger residential in-ground swimming pools

Pool systems requiring a high-capacity sand filter

Customers upgrading to a 2" top-mount valve setup

Pool owners looking for simple backwash maintenance

Replacement for Hayward S310T2 / W3S310T2 style filters

Key Features

Large 31" Class Sand Filter Tank: The large filter tank provides high-capacity sand filtration for larger pool systems and helps maintain clean, clear water.

2" VariFlo Multiport Valve Included: The included 2" top-mount VariFlo valve allows easy control of filter functions, including filter, backwash, rinse, waste, recirculate, closed, and winter settings.

Durable Corrosion-Proof Construction: The unitized filter tank is molded from rugged, colorfast polymeric material for dependable outdoor performance and long-lasting use.

500 lb Sand Capacity: The large sand bed helps capture dirt and debris effectively, supporting reliable everyday filtration.

Even Water Distribution: The integral top diffuser distributes water evenly across the sand media bed for improved filtration performance.

Self-Cleaning Lateral System: Precision-engineered umbrella-fold laterals provide balanced flow, efficient backwashing, and easier serviceability.

360-Degree Valve Rotation: The flange clamp design allows the valve to rotate 360 degrees, helping simplify installation and plumbing alignment.

Easy Service and Winterizing: A large pressure sand and water drain helps make draining, servicing, and winter preparation faster and more convenient.

Benefits

The Hayward W3S310T2 is built for pool owners who want strong filtration performance with low-maintenance operation. Sand filters are easy to operate, simple to backwash, and do not require frequent cartridge cleaning or replacement.

With its 2" VariFlo valve, 500 lb sand capacity, 4.91 sq. ft. filtration area, and 98 GPM flow rate, this model is a strong option for larger residential pool systems when properly matched with the pump and plumbing.

Specifications

What’s Included

• Hayward W3S310T2 ProSeries sand filter tank
• 2" top-mount VariFlo multiport valve
• Filter base
• Internal lateral assembly
• Pressure gauge

Pool filter sand is not included.

Customer-Facing Q&A

Q: Does this filter include the valve?
A: Yes. The Hayward W3S310T2 includes a 2" top-mount VariFlo multiport valve.

Q: How much sand does this filter require?
A: This filter requires 500 lbs. of #20 silica pool filter sand.

Q: Is sand included?
A: No. Filter sand must be purchased separately.

Q: What is the flow rate?
A: The Hayward W3S310T2 has a listed flow rate of 98 GPM.

Q: Is this a top-mount or side-mount filter?
A: This is a top-mount sand filter.

Q: What is the difference between W3S310T2 and W3S310S?
A: The W3S310T2 is a top-mount sand filter with a 2" VariFlo valve included. The W3S310S is a side-mount filter tank and typically requires a separate side-mount valve.

Q: Is this filter suitable for larger residential pools?
A: Yes. The large tank, 500 lb sand capacity, and 98 GPM flow rate make it suitable for larger residential pool systems when properly matched with the pump, plumbing, and pool size.

Q: How do I clean this filter?
A: Cleaning is done by backwashing through the multiport valve. Backwash when the pressure gauge rises approximately 8–10 PSI above the clean starting pressure.

Q: Does this filter include a pressure gauge?
A: Yes. A pressure gauge is included.