Filling The Heating System; Check All Connections On The Heating Water Side For Tightness - Viessmann Vitoligno 300-C Installation And Service Instructions For Contractors

Filling the heating system

Fill water
!
Please note
Unsuitable fill water increases the level of
deposits and corrosion and may lead to appli-
ance damage.
■ Flush the heating system thoroughly before
filling.
Only use fill water of potable water quality.
■
Special antifreeze suitable for heating systems
■
can be added to the fill water. The antifreeze
manufacturer must verify its suitability.
■ Fill and top-up water with a water hardness in
excess of the following values must be soft-
ened, e.g. with a small softening system for
heating water.
Total permissible hardness of the fill and top-up water
Total heating output
kW
50
≤
Fig. 20
1. Check the pre-charge pressure of the expansion
vessel.
If the pre-charge pressure is lower than the static
system pressure, top up with nitrogen until the pre-
charge pressure is 0.1 to 0.2 bar (10 to 20 kPa)
higher than the static system pressure.
If the pre-charge pressure is too high, adjust it
accordingly.

Check all connections on the heating water side for tightness

Specific system volume
< 20 l/kW
3
3.0 mol/m (16.8 °dH)
≤
Commissioning, inspection, maintenance
20 l/kW to < 50 l/kW
≥
3
2.0 mol/m (11.2 °dH)
≤
2. Open the non-return valves.
3. Fill the heating system with water and vent until the
charge pressure is 0.1 to 0.2 bar (10 to 20 kPa)
higher than the pre-charge pressure of the expan-
sion vessel.
Permiss. operating pressure: 3 bar (0.3 MPa)
Test pressure: 4 bar (0.4 MPa)
4. Mark the charge pressure at pressure gauge
5. Return the non-return valves to their operating posi-
tion.
Note
The boiler expansion vessel connection must not be
—
interrupted with shut-off valves.
50 l/kW
≥
3
< 0.02 mol/m (0.11 °dH)
.
A
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