Air Valves are an essential element of any potable or wastewater system. Without Air Valves, air pockets will form, restricting the pipeline and therefore reducing flow and increasing energy costs. Furthermore, air pockets have been found to be a significant causal factor in the build-up of corrosive substances, such as hydrogen sulphide, which essentially will lead to high maintenance costs or pipeline collapse.

It is recommended Air Valves are installed every ½ mile on a straight horizontal pipeline, and on every high point greater than one pipe diameter where the pipeline converts from a positive grade to a negative grade.

Why Air Vacuum Valves?

Air Vacuum valves are used to exhaust large quantities of Air upon system start-up, and allow air to re-enter the line upon system shut down or system failure. The valve remains closed when the system is under pressure.



An added benefit of an Air Vacuum valve is its ability to provide pipeline vacuum protection. If a negative pressure develops, the valve will open, admitting air into the line. This reduces the potential for surges and collapse of pipelines.

Why Air Release Valves?

As Air Vacuum valves do not continuously release Air during operation (they only release large quantities of air upon system start-up and shut-down), in systems where this is a requirement, an Air Release Valve is required too.



Air Release valves continuously release accumulated air during system operation; as air enters the valve, the float drops, releasing air into the atmosphere. As air is released it is displaced by water which raises the float and closes the valve.

Why Combination Air Valves?

Combination Air valves perform the functions of an Air Vacuum valve and an Are Release valve, meaning large quantities of air is released on system start-up and system shut-down, as well as air continuously being released during operation.


Val-Matic provide MGA Controls with a range of Air Vacuum, Air Release and Combination Valves in various sizes, materials and with various functions. Val-Matic’s range of Air Valves have unique features making them highly suited to potable and wastewater applications, such as stainless steel guided floats and trim and fusion-bonded epoxy coatings.


For more information on our range of Air Valves, or for specific information relevant to your unique application, please phone our technical team on +44 (0) 870 803 2001 – we have plenty of case studies which we can offer you.