There Is No Hot Water; The Dhw Is Too Hot; Fault" Is Shown In The Display - Viessmann VITOLIGNO 300-C Operating Instructions Manual

There is no hot water

Cause
Control unit incorrectly set.
DHW cylinder is cold.
The DHW cylinder pump is not running.
Mixing valve faulty

The DHW is too hot

Cause
Control unit incorrectly set.
Sensor fault

"Fault" is shown in the display

Cause
Heating system fault
Remedy
Check the settings and correct if required:
DHW heating must be ON (see page 25)
■
DHW temperature (see page 25)
■
Time (see page 35)
■
Switching times (see page 25)
■
Check the DHW heating times (see page 25)
Check the set DHW temperature (see page 25)
If the heating times are OK: check the temperature of
the DHW cylinder.
If that is too low: notify your heating contractor.
Check the heating times. If the pump is running accord-
ing to the times set in the control unit: notify your heat-
ing contractor.
Notify your heating contractor.
Remedy
Check and correct the DHW temperature if required
(see page 25).
Notify your heating contractor.
Remedy
Check the type of fault (see page 38) and notify your
heating contractor.
What to do if...
43