VAG Operation and Maintenance Instructions • 5
lic stop. While doing so make sure that the safety ring (19) locks
into place and that it is seated on the socket on the face side. You
may need to manually push it down. Check the function of the
interlock by turning it back.
Pull down the protective rubber lining (20) over the 3 cams located
on the outside of the socket.
Picture 3: Detailed view of spigot version
19
20
Before filling in the pipe trench install the appropriate VAG seepa-
ge stone for the safe draining of the underground hydrant.
In addition, observe the installation guidelines set out in DVGW
worksheet W 331 to install the HYDRUS
®
G.
Picture 4: Seepage stone
Seepage stone
5 Set-up and operation of the valve
5.1 Visual inspection and preparation
Before putting the valve and the equipment into operation, per-
form a visual inspection of all functional parts.
The fittings are sufficiently lubricated at the factory for purposes of
assembly, storage and transport. For maintenance work specified
in accordance with M 392 the lubricant for drinking water lines
approved for foodstuffs or drinking water,
• KLÜBERSYNTH VR 69-252 N (with KTW approval for drinking
water) manufactured by Klüber Lubrication München AG,
must be used.
5.2 Function check and pressure test
Prior to installation the working parts of the valve must be ope-
ned up completely and closed at least once and the movement
checked.
Caution!! During a pressure test of the pipeline the
closed valve may only be put under a load up to its no-
minal pressure (see technical data sheet KAT 1161-A).
Caution!! According to the technical standard a leaka-
ge rate of only E in accordance with DIN EN 1226-1 is
guaranteed for the draining seal that is active when the
cone is open. This means that there is no tightness gu-
arantee on the part of the manufacturer for a pressure
test in this position.
For test pressures higher than the approved nominal pressure the
hydrant must be disassembled and the flange blanked using a
blind flange .
Newly installed pipeline systems should first be carefully flushed
to remove all foreign matter. Should any residue or impurities exist
in the pipeline they may clog the internals during the flushing pro-
cess. This may impact the tightness function of the fitting or da-
mage the lining of the shut-off cone.
In particular, after repairs are carried out, but before putting new
systems into operation, the pipeline system must be flushed again
with a fully opened valve. Any cleaning or disinfecting agents used
may not corrode the fitting materials. The fitting is normally closed
by being turned in clockwise direction.
5.3 Initial operation
VAG HYDRUS
®
G Underground Hydrants are delivered in versi-
ons with
a) self-closing outlet claw cover (2.1)
b) claw, muzzle protector and plastic cover (2.2).
Installation of the standpipe must be carried out according to the
version of claw used.
Lift up self-closing outlet claw cover (2.1), or remove plastic out-
let claw cover (2.2). Attach and tighten standpipe. Check that the
base pins are properly seated in the claw (1.1) by shaking the
standpipe.
Fill the piping section. In doing so the underground hydrant can be
used to release air and be flushed afterwards.
Caution!! The hydrant shut-off valve must always be
completely open. Throttling of the flow may only take
place via the valves on the standpipe.
Throttling the hydrant shut-off valve may result in high
flow velocities occurring within the valve
