Proper air management inside a pool filter is critical to both system safety and filtration performance. The Swimables Pentair Style Air Relief Valve (SW-26-908) is a direct-replacement component designed to safely release trapped air from Pentair-style pool filters during startup, maintenance, and normal operation.

When air becomes trapped inside a pressurized filter tank, it compresses as the pump ramps up, creating unstable pressure conditions that can affect filtration efficiency and place unnecessary stress on internal components. Without a functioning air relief valve, pressure may spike suddenly, readings may become unreliable, and the filter may not operate within its designed safety range. The SW-26-908 restores controlled air venting so pressure stabilizes correctly before the system reaches full flow.

This manual air relief valve installs directly into compatible filter lids and is engineered to match Pentair-style specifications. It is commonly used as a replacement when the original valve becomes cracked, seized, brittle, or difficult to operate due to age, chemical exposure, or repeated service cycles. Whether you’re performing routine maintenance or correcting a startup issue, this part plays a critical role in protecting the filter and ensuring consistent performance.

How Air Relief Affects Pool Filter Safety and Performance

Every time a pool system starts, air is introduced into the plumbing and filter tank. This is especially common after filter cleaning, cartridge replacement, DE grid service, or any time the system has been opened. As the pump begins circulating water, that trapped air must be released in a controlled manner.

A properly functioning air relief valve allows air to escape gradually until the tank fills completely with water. Once water flows steadily from the valve, the system has reached a stable, fully flooded state. At that point, the valve can be closed and the filter can operate safely at normal pressure.

Without proper air relief, trapped air can compress rapidly. This can cause inaccurate pressure behavior, strain internal components, and increase the risk of leaks or seal failure. The Swimables SW-26-908 ensures that air is released the way the filter manufacturer intended.

Designed for Pentair-Style Pool Filters

The SW-26-908 is manufactured to Pentair-style dimensions and threading, making it compatible with several of the most common residential and light-commercial pool filters on the market.

This valve is commonly used on filters that rely on a manual air relief system rather than a spring-loaded or automatic design. Its simple construction makes it reliable, easy to service, and easy to operate during startup and maintenance.

Because it installs directly into the filter lid, there is no need for adapters, plumbing modifications, or special tools. This makes it a practical replacement for service technicians and experienced pool owners alike.

When to Replace an Air Relief Valve

Air relief valves are exposed to constant pressure, moisture, chemicals, and outdoor conditions. Over time, even high-quality valves can degrade. Replacing a worn valve proactively can prevent more serious filter issues down the line.

Common signs that an air relief valve should be replaced include persistent leaking around the valve body, difficulty turning or opening the valve, visible cracks or brittleness in the plastic, or failure to vent air during startup. In some cases, a valve may appear functional but no longer seal correctly once closed, leading to slow pressure loss.

Installing a new Swimables SW-26-908 restores proper function and helps ensure safe, predictable filter behavior after every service cycle.

Durable Construction for Pool Environments

Pool equipment operates in harsh conditions. Chlorine, salt systems, heat, UV exposure, and pressure cycling all take a toll on plastic components. The SW-26-908 is manufactured using chemical-resistant materials designed specifically for pool filtration systems.

The valve body is engineered to maintain structural integrity under pressure while remaining easy to operate by hand. This balance of strength and usability is essential for components that are opened and closed regularly during maintenance.

Unlike aging factory valves that may become brittle or seize over time, this replacement valve is built to provide consistent operation across repeated startup cycles.

Installation Overview

Replacing the air relief valve is a straightforward process for most pool professionals and mechanically inclined pool owners.

Before installation, the pump should be turned off and system pressure fully relieved. The old valve can then be removed from the filter lid and replaced with the SW-26-908. Once installed, the valve should be opened during startup to vent air until water flows steadily, then closed to allow normal filtration.

Proper installation ensures a tight seal without overtightening, which can damage the filter lid or valve threads.

Why a Proper Air Relief Valve Matters

• Safely releases trapped air during startup and after service

• Prevents sudden pressure spikes inside the filter tank

• Supports consistent, predictable filtration performance

• Reduces stress on filter internals and seals

• Essential for safe operation after cleaning or maintenance

This small component plays a large role in protecting your filtration system.

Product Specifications

Buy with Confidence from Benchmark Pool Supply

When you purchase the Swimables Pentair Style Air Relief Valve (SW-26-908) from Benchmark Pool Supply, you’re buying from a real pool supply company that understands how these parts are used in the field.

We stock proven service components, verify compatibility, and support both homeowners and pool professionals. Our goal is to help keep filtration systems operating safely, efficiently, and reliably — not just sell parts.