Air vent valves (also known as automatic air vent or auto vent or Air release valves and even mistakenly referred as air relief valve) are commonly used in pressurized systems to bleed the air which gets trapped in it due to emptying of pipes especially after downtime of the hydro-pneumatic / chiller pump. Similarly in gravity fed systems also when the pipe forms an inverted u shaped bend air is trapped whenever the elevated/ overhead tank becomes empty.

The varie AV21 is a simple solid float design Air Vent. The transparent chamber makes it the worlds most unique air vent that gives a visual indication of performance. This comes with the optional auto shut off valve which saves cost of a ball valve and is a super saver.