The automatic airvent is used in hdyronic systems to release the entrapped air. It is installed at all the high points in the system where there is a likelihood of air entrapment.

The float of the airvent keeps the venting valve closed. When air is collected inside the float chamber, the water level inside the airvent decreases and the venting valve opens. The collected air escapes through the venting valve and the water level inside the airvent increases again, which in turn results in closing of the venting valve. This process is continuous as long as air is collected in the airvent.

When pressure inside the system decreases below the ambient pressure, for instance during draining of the system, the airvent acts as a vent.

-	Reduced corrosion
-	Better system efficiency
-	No air locks