VAG Operation and Maintenance Instructions • 7
Permissible
Impermissible
Upright
installation
position
Picture 10: Installation position of the Automatic Air Valve
90°
<> 90°
4.4.1 Installation position downstream from
pumps
If the VAG DUOJET
®
Automatic Air Valve has to be installed
downstream from pumping stations, positioning must take place
according to the “ideal” installation position shown in Picture 11.
Picture 11: Installation position downstream from pumps
Impermissible
installation position
Ideal installa-
tion position
4.4.2 Installation in standpipes
Standpipes result in high flow velocities during the filling process.
If the VAG DUOJET
®
Automatic Air Valve is installed directly on
the standpipe there is a risk of the ball closing prematurely.
To prevent premature closing we recommend the installation of a
multiple-orifice plate in front of the valve (cf. Picture 12).
4.4.3 Discharging splashing or surge water
When intentionally discharging splashing or surge water via the
pipeline it should be cut off slowly downstream of the valve so
that no improper suction effect impacts the VAG DUOJET
®
Auto-
matic Air Valve (cf. Picture 13).
Picture 12: Installation position in standpipe
Impermissible ins-
tallation position
(risk of suction effect)
Ideal installation position
(elbow and down-pipe separated)
Picture 13: Installation position for splashing or surge water
Multiple-orifice plate
