How to Choose an Air Release Valve for Water Lines

Introduction

Air release valves play a crucial role in maintaining the efficiency, safety, and longevity of pressurized water systems. Whether used in municipal water mains, agricultural irrigation networks, or wastewater treatment pipelines, choosing the right air release valve can significantly impact system performance and maintenance costs.

This guide explains the functions, types, and selection criteria for air release valves for water lines, helping engineers, technicians, and buyers make informed decisions for various applications.

What Is an Air Release Valve and How Does It Work?

An air release valve is a device installed on top of a pipeline to automatically release trapped air during system operation. As air accumulates at high points in the water system, it can restrict flow, increase pressure, or even cause pipe damage. The air release valve for water is designed to expel these air pockets safely and efficiently without manual intervention.

There are three main types:

Automatic air release valves – continuously release small pockets of air.
Air/vacuum valves – allow large volumes of air to enter or exit during filling or draining.
Combination air valves – combine both functions for comprehensive protection.

Why Air Traps Are a Problem in Water Lines

When air becomes trapped in water mains, it can form air locks, cause flow disruptions, and result in surging or water hammer. Over time, this reduces system efficiency and increases wear on equipment.

Especially in long-distance water lines, air release valves for water lines are critical to ensure stable pressure and flow. A properly selected water air release valve reduces operational interruptions and enhances pipeline longevity.

In municipal systems, using a dedicated air release valve water main model helps maintain a consistent water supply and protects infrastructure from damage caused by pressure imbalance.

Key Factors in Choosing an Air Release Valve

1. Pipeline Type and Application

Not all pipelines are the same — select the valve based on the medium and system function:

For clean water supply, choose stainless steel or epoxy-coated air release valves for water.
In sewage pipelines, select a sewage air release valve with anti-clogging features and chemical resistance.
For irrigation systems, use an irrigation air release valve designed to handle variable flow and sediment content.

2. Operating Pressure and Flow Rate

Ensure that the selected valve matches your system’s operating pressure. Most air release valve for water models operate in the 1.0–1.6 MPa range. Under- or over-specifying pressure tolerance may cause leakage or premature failure.

3. Material Selection

For general use, ductile iron and stainless steel offer strength and durability. In aggressive environments like wastewater treatment, select air release valves for water with corrosion-resistant coatings and internally lined epoxy.

4. Mounting Location

Correct installation is essential for performance. Place air release valves:

At high points in pipelines
Downstream of pumps
Before and after control valves and meters
Along long horizontal runs to prevent air accumulation

Proper placement ensures stable operation and prevents pressure surges and vacuum collapse.

Popular Applications of Air Release Valves

Municipal Water Distribution

Use a water air release valve or air release valve water main configuration to maintain consistent pressure and eliminate trapped air in large city pipelines.

Agricultural Irrigation Systems

Install an irrigation air release valve in drip or sprinkler networks to prevent uneven flow, reduce downtime, and protect emitters from clogging.

Wastewater and Sewage Lines

A sewage air release valve is critical in low-flow or sludge-heavy pipelines. These valves prevent gas buildup, reduce odor emissions, and improve system reliability.

Benefits of Using Air Release Valves for Water Systems

Implementing the right air release valves for water systems offers several key advantages:

Prevents pipeline air locks and flow disruptions
Minimizes pressure surges and water hammer
Extends lifespan of pumps, pipes, and control valves
Improves hydraulic efficiency
Reduces long-term maintenance and operational costs

Conclusion: Select the Right Valve for the Right Job

Choosing the correct air release valve is about more than just part numbers — it requires understanding your system’s pressure, environment, and pipeline layout. The right valve protects your investment and ensures uninterrupted operation.

At Xhy Valve, we offer reliable, cost-effective solutions including:

Air release valve for water line
Water air release valve for irrigation systems
Sewage air release valve with advanced clog prevention

👉 Browse Our Full Range of Air Release Valves
👉 Download the Xhy Valve Product Catalog

FAQ

What is the purpose of an air release valve in a water system?

An air release valve removes trapped air from pipelines to maintain proper flow, reduce pressure surges, and prevent damage to pumps and pipes.

How does an air release valve work?

The working principle of an air release valve involves detecting air pockets at high points in a water line and automatically opening a vent to release air. Once the air is expelled, the valve closes to maintain system pressure.

Can the same valve be used for both water and sewage systems?

No. While water pipelines use standard air release valves for water, sewage air release valves must include clog-resistant mechanisms and corrosion-proof materials due to harsh media.

Where should I install an irrigation air release valve?

In irrigation systems, install the irrigation air release valve at elevated points, near filters, and downstream from pumps to eliminate trapped air and prevent inconsistent watering.

What are typical specifications for an air release valve?

Common air release valve specifications include working pressure (e.g., 1.0–1.6MPa), body material (ductile iron, stainless steel), connection type (flanged/threaded), and flow capacity. These vary based on application—clean water, irrigation, or sewage.

What is the working principle of an air release valve?

The working principle relies on float-based or diaphragm mechanisms that respond to the presence of air. As air collects, the valve opens; once water rises to displace air, the valve closes automatically to seal the system.