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Air Valves

Dezurik carries a full line of APCO air valves ranging from clean water air release to wastewater combination.

All valves are available to meet American Iron and Steel requirements and have a long history of dependable service.

Tek-Sales performs air valve sizing regularly for many projects and can provide a full report at no cost.



The APCO Clean Water Air Release Valves (ARV) function to release air pockets that collect at each high point of a pressured pipeline, and are essential for pipeline efficiency and water hammer protection. Air Release Valves are available in a wide variety of orifice sizes and materials of construction to meet a wide range of applications.

Air/Vacuum Valves are float operated and have a large discharge orifice equal in size to the valve’s inlet. Air/Vacuum valves allow large volumes of air to be exhausted from or admitted into a pipeline as it is being filled or drained. As the pipeline fills, fluid enters the valve, raises the float, and shuts-off. When draining the pipeline, the float drops and allows air to enter, preventing a vacuum and possible pipeline collapse or damaging water column separation.

The AVV can also be configured as a Dual Body Combination Air Valve with an ARV Air Release Valve. The AVV Dual Body Combination Air Valve combines the functions of both an Air/Vacuum Valve to expel large volumes of air during filling or draining of the pipeline, along with an Air Release Valve to release small quantities of air during normal operation. Combination Air Valves are typically installed on all high points of a system where it has been determined that the functions of both an Air/Vacuum Valve and an Air Release Valve are needed to vent and protect a pipeline.


Combines the features of Air/Vacuum Valves and Air Release Valves. These valves are also called Double Orifice Air Valves. They are installed on all high points of a system where it has been determined dual function Air/Vacuum and Air Release Valves are needed to release air and also protect a pipeline from a vacuum. Combination Air Valves are available in 2 body styles - 1) single body combination or 2) custom-built combination with two bodies. The single body combination is used where compactness is preferred. Generally, it is sound engineering practice to use Combination Air Valves instead of simple purpose Air/ Vacuum Valves.



APCO Single Body Combination Air Valves (ASU) can be used for clean or dirty services. The unique and patented venting design provides varied and predictable airflow over a wide range of air release and air/vacuum conditions. A large diameter Air/Vacuum Disc provides high volume airflow for rapid venting during pipeline filling and allows high volumes of air to enter the pipeline during draining. During normal pipeline flow conditions, the dual-range air release design prevents air build-up and resultant flow restrictions under changing conditions and through the full flow range. 

All 316 stainless steel construction and without troublesome linkages this valve automatically adjusts for air release eliminating the need for sizing this function. Inlet and outlet are the same size per AWWA allowing the best vacuum relief in the industry.



Because sewage media generates large quantities of gas, the potential for air entrapped with sewage pipelines is even greater than in water lines. It is recommended that each high point be protected with a Sewage Air Release Valve. The elongated body of the Sewage Air Release Valve minimizes clogging by permitting use of a much longer float stem to prevent the sewage from fouling up the mechanism.

Single and Dual Body Sewage Combination Valves


Sewage combination air valves operate the same as Air Valves for Water, differing only in appearance with elongated taller bodies. Elongated bodies minimize clogging by permitting use of a much longer float stem, to prevent the sewage from fouling up the mechanism. For ease of maintenance, Flushing Attachments are recommended with the Valves, as shown. When adding Sewage Air Valves to your pipeline, the same criteria applies, as with the standard Air Valves. However, the potential for air entrapped with Sewage pipelines is even greater than that found in water lines, because Sewage media generates large quantities of gases. Therefore, it is recommended each high point be protected with an automatic Sewage Air Release Valve.

APCO ASV Sewage Air Valves are specifically designed for operation on sewage and waste media. Air/Vacuum Valves vent large volumes of air when the sewage line is filled and allow air to re-enter when draining, to prevent vacuum or column separation from occurring. Sewage Air/Vacuum Valves utilize two floats, each connected to a common stem which is guided through a bushing. The upper float shuts off instantaneously against the seat, due to the impact zone and lifting force of the much larger concave bottom float, as sewage media enters the valve body. Once closed and pressurized, the Air/Vacuum Valve will not open to release air. It will open under negative pressure allowing air to re-enter and prevent vacuum from forming in the line. The ASV-401C Air/Vacuum Valve has an independent, side-connected Air Release Valve. The ASV-401C provides dual functions: venting large volumes of air through the large orifice and releasing small pockets of air through the small orifice air release valve.

APCO AVR 1500A Vacuum Relief/Air Inlet Valves are proven reliable at preventing vacuum formation in pipelines and resulting damage from column separation and water hammer (pressure surges). They are normally closed, large orifice one-way valves. They permit air to enter the pipeline or system to break a vacuum, but no air escapes when the system pressure returns to positive. They are available in sizes 3-24” (80-600mm) and are recommended for either water or sewage applications.

The AVR is also available as a 1500AC Combination Valve, with the large orifice Vacuum Relief/Air Inlet Valve opening quickly to prevent a vacuum while the small orifice Air Release Valve regulates a slow discharge of air from the pipeline.


Vacuum Relief/Air Inlet Valves are normally shut for prolonged periods of time, and often not readily accessible for inspection. Therefore, it is critically important to select a reliable, high quality valve. The APCO AVR Vacuum Relief/Air Inlet Valve consists of the highest quality components: body, cover, plug, seat, stainless steel spring, and a hood or cap to prevent debris from entering the valve.


The APCO Surge Check Valve is designed to prevent critical shock conditions occurring in installations where the operating conditions could cause a regular Air Vacuum Valve to slam open and/or closed. The Surge Check Valve is bolted to the inlet of an APCO AVV Air/Vacuum Valve to protect it from slam. The Surge Check Valve may be purchased as a complete assembly or purchased separately to add to a previously installed air/vacuum valve. Because the Air/Vacuum Valve and the Surge Check unit are each self-contained items, the Surge Check can be added to any Air/Vacuum Valve already in service, making it into a Slow Closing Air Vacuum Valve. CSV Surge Check Valves are available in sizes

1-18” (25-450mm)


Air/Vacuum Valves efficiently discharge air from deep well pump columns when combined with an APCO Double-Acting Throttling Device (DAT). The DAT has an exclusive Throttling Air-Out/Full Flow Air-In design. Regardless of the amount of air throttling out, there is assured full line capacity air inflow on pump stop to prevent vacuum and water column separation. Available on valves sizes 0.5-8” (15-200mm), the DAT is fitted on the discharge orifice of the Air/Vacuum Valve. Because the pipeline media does not contact the Double Acting Throttling Device, it can be used on pipelines containing dirty fluids.

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