Viessmann VITOCAL 151-A Installation And Service Instructions Manual page 76

Commissioning, inspection, maintenance
Filling the system
3. Open the outdoor unit 3-way flow and return ball
valve as shown in Fig. 75: Open in all directions
Allow the heating water to flow in via the fill hose.
!
Please note
Unsuitable fill and top-up water increases
the level of deposits and corrosion. This can
reduce the output of the heat pump or cause
damage to the system, in particular to the
integral instantaneous heating water heater.
■ Flush the heating system thoroughly
before filling.
Only fill with water of potable quality.
■
Only use fill and top-up water with a hard-
■
ness of < 3 °dH.
Heating water flow rate:
■ Min. 600 l/h
Max. 1500 l/h
■
Charge pressure: Min. 0.2 bar (0.02 MPa) above
the pre-charge pressure of the expansion vessel
Factory-set pre-charge pressure of expansion ves-
sel: 0.75 bar (0.075 MPa) to 0.95 bar (0.095 MPa)
Calling up the filling function
To activate this function, start the commissioning assis-
tant.
76
(cont.)
4. Start the filling process in the commissioning assis-
tant.
The filling of the 1st consumer circuit begins.
5. As soon as air bubbles are no longer coming out of
the drain hose, start the filling of the next consumer
circuit with
6. After filling all consumer circuits, end the filling
process with
The commissioning assistant switches to building
up the system pressure.
7. Close both the 3-way ball valves.
8. Remove the fill and drain hoses.
See page 73.
.
.