Instructions on commissioning, maintenance, and troubleshooting for auroSTOR 0020111119_02
31
6.6
Installation of cold mains inlet
6.6.1
Pressure in cold mains inlet
The efficiency of an unvented cylinder depends on the
available pressure in the cold mains inlet and the flow
rate. To obtain optimum cylinder output, there must be
a suitable cold mains inlet, i.e. the measured static line
pressure must be at least 2.0 bar. A corresponding flow
rate of at least 20-25 l/min must be available.
i
The pressure in the cold mains inlet will be
reduced at times of high consumption. Thus,
measurements should be taken at such times.
The cylinder still works satisfactorily with a pressure
below 2 bar but the flow rate is reduced. If the pressure
is below 1 bar, you should not install an unvented cylin-
der. Vaillant Ltd. can provide information on alternative
hot water supply systems.
80
4
5
60
3
40
2
Inlet pressure (bar)
Flo
w r
at
e (l/
min
)
20
1
0
Fig. 6.7 Maximum flow rate of the cold water assembly based
on the supply pressure
The displayed flow rates apply to installations in which
the cold water supply has a dynamic pressure and flow
rate appropriate for the system.
If the static water pressure is less than 1 bar, contact
Vaillant Ltd.
6.6.2 Mounting the safety assembly
b
Caution!
Risk of damage to the cylinder as a
result of excess pressure!
Excess pressure can cause the cylinder
to burst.
>
Make sure that there is no stop valve ins-
talled between the safety assembly
and the cylinder.
1
2
3
4
5
7
6
Fig. 6.8 Safety assembly
Key
1 Pressure reducing valve with line strainer
2 Cold water inlet
3 Pressure-controlled cold water inlet
4 Cylinder
connection
5 Hot water expansion vessel connection
6 15 mm expansion relief valve connection
7 Expansion relief valve
>
During the installation process, position the valves so
that you are able to connect the 15 mm connection (
6
) of
the expansion relief valve (
7
) with the tundish. Note the
direction of flow, which is marked on the safety assembly
with arrows.
i
The safety assembly must be installed horizon-
tally with the expansion relief valve facing
upwards (
¬ Fig. 6.8
) in order to prevent the
build-up of dirt.
b
Caution!
Risk of damage to the cylinder as a
result of excess pressure!
Excess pressure can cause the cylinder to
burst.
>
Make sure that the expansion relief valve
outlet is not covered or closed.
Installation 6
