Air release valves are used in pressurized pipe work systems to vent off unwanted air within them. Trapped air rises and collects within the high points of the system.
As air vented water fills the valve, the float rises until the valve seat is pushed back against the orifice closing it off from atmosphere again.
Valves are customizable with options such as a variable throttle device to give adjustable venting control, inflow and outflow check device for one-way airflow and flanged outlet for piping away facility.
Credits: frenstarvalves