13
1.
Check the heating system pressure
at pressure gauge
A
:
The system pressure is too low if the
indicator points to the area below the
red field. Top up with water or notify
your local heating contractor.
Minimum system pressure: 1.0 bar
(0.1 MPa)
2.
Check that the vents of the installa-
tion room are unrestricted.
Note
With open flue operation, the com-
bustion air is drawn from the installa-
tion room.
3.
Verify that the heating system or the
heating water buffer cylinder is draw-
ing off heat. Open the thermostatic
valves on the radiators if necessary.
4.
Ensure that all heating flow and heat-
ing return shut-off gate valves are
open.
5.
Check that all covers on the boiler are
closed.
6.
Ensure that power is supplied to the
boiler.
Action in case of overheating
The high limit safety cut-out protects
your boiler from overheating.
Note
Modifications to these components, of
any kind whatsoever, are prohibited and
will render all warranties void.
Replace faulty components only with
genuine spare parts from Viessmann.
Boiler operation
Heat-up preparations
5549 811 GB
Summary of Contents for Vitoligno 300-H
Page 71: ...71 5549 811 GB...
