53
Flow limiter
Serial no.
(type plate)
Flow rate
l/min
Colour
7723181
7722712
10 (GB)
Light blue
7544691
7544693
7722696
7722701
7722222
7720292
7723182
7722713
12
Red
7544692
7544694
7722697
7722702
7722223
7720293
7723183
7722714
14
Pink
7544695
7722703
7722224
7720294
16
Blue
Checking the expansion vessel and system pressure
Note
The expansion vessel can lose some of its charge
pressure over time. When the boiler heats up, the
pressure rises to 2 or 3 bar (0.2 or 0.3 MPa). The
safety valve may also respond and discharge the
excess pressure.
Therefore check the expansion vessel pre-charge
pressure annually.
Check whether the installed expansion vessel is ade-
quate for the system water volume.
Carry out this test on a cold system.
1.
Drain the system until "0" is shown on the display.
Note
For pressure indicator on the home screen,
repeatedly until the pressure gauge symbol is
displayed.
2.
If the pre-charge pressure of the expansion vessel
is lower than the static system pressure: Top up
with nitrogen at the valve of the diaphragm expan-
sion vessel until the pre-charge pressure is 0.1 to
0.2 bar (10 to 20 kPa) higher than the static system
pressure.
3.
Top up with water until the charge pressure of the
cooled system is at least 1.0 bar (0.1 MPa), and is
0.1 to 0.2 bar (10 to 20 kPa) higher than the pre-
charge pressure of the expansion vessel.
Permiss. operating pressure: 3 bar (0.3 MPa)
Note
The expansion vessel is supplied from the factory
with a pre-charge pressure of 0.7 bar.
Do not allow the pre-charge pressure to fall below
this value (boiling noises). This also applies to sin-
gle floor heating systems or attic heating centres
(no static pressure).
Top up with water until the charge pressure is 0.1
to 0.2 bar above the pre-charge pressure.
Commissioning, inspection, maintenance
Checking the flow limiter (only for gas…
(cont.)
6167586