Restore Safe Pressure Release and Proper Startup on Sand Filters

Air trapped inside a sand filter tank can cause pressure spikes, inconsistent flow, and unreliable filtration. The Swimables SW-26-564 Pentair® Style Sand Filter Air Relief Assembly with Nut is a critical safety and performance component designed to release trapped air during startup and operation of compatible Pentair-style sand filters.

This air relief assembly allows accumulated air to escape from the top of the filter tank so the system can prime correctly and operate under stable pressure. When the air relief fails, filters may surge, show erratic pressure readings, or struggle to circulate water efficiently. Replacing a worn or damaged air relief assembly restores proper pressure behavior and helps protect the filter tank and internal components.

This is a pool-specific sand filter air relief assembly, not a generic plumbing vent or valve.

What a Sand Filter Air Relief Assembly Does

During startup or after maintenance, air becomes trapped inside the filter tank. The air relief assembly provides a controlled escape path for that air so water can fully fill the tank.

A properly functioning air relief assembly:

• Releases trapped air during pump startup

• Prevents pressure spikes inside the filter tank

• Helps establish proper filtration flow

• Stabilizes pressure gauge readings

• Protects internal laterals and plumbing

Without a working air relief, air pockets can compress under pressure, leading to noisy operation, reduced filtration efficiency, or stress on the tank.

Air relief service is often performed alongside components from the Pool Filter Parts Collection.

Pentair® Style Sand Filter Compatibility

The Swimables SW-26-564 is engineered as a Pentair-style sand filter air relief assembly, designed to match the form and function used on many Pentair sand filter platforms.

Compatibility highlights include:

• Pentair-style sand filters

• Top-mounted air relief port designs

• Proper thread sizing and sealing surface

• Includes retaining nut for secure installation

This assembly is intended for style compatibility, meaning it mirrors the physical configuration used on compatible Pentair sand filter tanks.

Includes Retaining Nut for Secure Installation

Unlike partial replacements, the SW-26-564 includes the air relief assembly with nut, ensuring proper clamping force and long-term sealing.

Benefits of the included nut:

• Proper compression against the tank wall

• Reduced risk of leaks

• Secure fit during pressure cycles

• Simplified replacement without sourcing extra parts

A loose or damaged retaining nut is a common cause of persistent air leaks, even when the relief valve itself appears functional.

Common Signs the Air Relief Assembly Needs Replacement

Air relief assemblies are exposed to pressure, vibration, and pool chemistry. Over time, seals wear out and plastic components weaken. Replace the air relief assembly if you notice:

• Air spurting from the top of the filter

• Persistent air bubbles returning to the pool

• Pressure gauge fluctuating or spiking

• Hissing sounds during startup

• Visible cracks or leaking around the relief port

Many filtration issues are incorrectly blamed on pumps or plumbing when the true issue is trapped air inside the filter.

If circulation issues persist, additional components in the Pool Filters Collection should be inspected.

Why Proper Air Relief Matters

Air is compressible—water is not. When air is trapped inside a pressurized filter tank, it creates unstable operating conditions.

A functioning air relief assembly:

• Allows safe venting of trapped air

• Prevents sudden pressure changes

• Reduces strain on filter tanks and plumbing

• Supports consistent filtration performance

• Improves overall system reliability

This makes the air relief assembly an essential safety and performance component, not an optional accessory.

Built for Sand Filter Operating Conditions

The Swimables SW-26-564 air relief assembly is manufactured specifically for swimming pool sand filter environments.

Design considerations include:

• Resistance to chlorinated and saltwater exposure

• Durable housing designed for pressure cycling

• Proper sealing geometry for filter tanks

• Reliable operation through repeated startups

These features ensure dependable performance in residential and light commercial pool systems.

Installation Considerations

Replacing a sand filter air relief assembly is typically straightforward but should be done carefully to ensure proper sealing.

General Installation Overview:

1. Shut off the pool pump

2. Relieve pressure from the filter tank

3. Remove the old air relief assembly

4. Install the new SW-26-564 assembly

5. Tighten the retaining nut evenly

6. Restart the system and verify air release

Over-tightening can damage the tank or seals, while under-tightening can cause leaks. Professional installation is recommended if you are unsure.

Ideal Applications

The Swimables SW-26-564 Pentair-style air relief assembly is ideal for:

• Pentair-style sand filters

• Filters experiencing trapped air issues

• Pressure instability during startup

• Preventative maintenance during sand changes

• Replacing cracked or leaking air reliefs

This part is commonly replaced during major filter service intervals.

Supports Overall Filtration System Performance

A properly vented sand filter operates more efficiently and safely. Restoring the air relief assembly helps protect:

• Filter tanks

• Pressure gauges

• Plumbing lines

• Pump seals

• Filtration consistency

For best system results, air relief service should be paired with circulation components from the Pool Pumps Collection.

Why Choose Swimables Replacement Filter Components

Swimables replacement parts are engineered to match OEM-style specifications while offering a cost-effective alternative to factory components.

Key advantages include:

• Accurate Pentair-style fit

• Pool-industry-specific materials

• Reliable pressure performance

• Compatibility with standard service practices

The SW-26-564 is a trusted solution for restoring safe and reliable sand filter operation.

Buy with Confidence from Benchmark Pool Supply

At Benchmark Pool Supply, we stock professional-grade pool filter components designed to maintain safe operation and dependable performance. The Swimables SW-26-564 Pentair® Style Sand Filter Air Relief Assembly with Nut is selected for accurate fit, durable construction, and long service life.

When you purchase from Benchmark Pool Supply, you receive:

• Pool-specific replacement components

• Clear compatibility guidance

• Fast shipping or convenient local pickup

• Support from knowledgeable pool professionals

We help ensure filter repairs are done right the first time.