172-65167MA-10 (VA1/VA3/VA4/VA5) 1 Oct 2021
4
Features
1. The air vent has no hinges or levers: the only moving part is the precision-ground
float, which eliminates concentrated wear and provides long service life.
2. Simple construction with few parts allows for easy maintenance.
Operation
Take measures to prevent people from coming into direct contact with
product outlets.
Failure to do so may result in burns or other injury from the discharge of fluids.
1. When water is transported, air inside the piping is forced
into the air vent by the pressure of the flow.
The float inside the air vent is in the lower position, thus
the valve is fully open and allows the air that enters the
air vent and fills the area around the float to then be
discharged.
2. When discharge is completed, as water flows into the air
vent, the rising water level causes the float to rise and to
close the valve.
If there is a rapid rise in water level (caused by rapidly
opening a shut-off valve, etc.), a small amount of water
may leak with discharged air immediately before the air
vent closes.
3. Once the valve closes after discharging initial air, it will
not open again, even if air accumulates inside the air
vent, until internal pressure drops to near atmospheric
pressure.
4. When draining the piping, the air vent automatically
opens to introduce air and remove water more easily
(preventing a vacuum from forming in the piping).
Air
Water
CAUTION
