Viessmann VITOLIGNO 300-C Installation And Service Instructions Manual page 97

Vitoligno 300-C Installation/Service
Fault Display
(continued)
Fault codes
Fault code displayed
0A
11
20
21
22
23
24
25
System characteristics
System circuits cannot be
controlled
Burner blocked
Burner blocked
Return temperature

raising facility valve
opening
Boiler circuit pump starts

Burner blocked
Burner blocked
Control unit set to 32°F
(0°C) outdoor temperature
No DHW heating
Calling up fault codes from the fault memory (fault history)
The 10 most recent faults are saved and can be called up.
Faults are sorted by date. The most recent fault is
given the fault number 1.
Press the following keys:
1. d + å simultaneously for approx. 4 sec.
The "Service" menu appears.
2. for "Fault history".
|/~
3. d to confirm.
4. for "Display".
|/~
5. ä until the default display is shown.
Deleting the fault codes from the fault memory
Press the following keys:
1. d + å simultaneously for approx. 4 sec.
The "Service" menu appears.
2. for "Fault history".
|/~
3. d to confirm.
4. for "Delete".
|/~
5. for "Yes".
|/~
6. d to confirm.
7. ä until the default display is shown.
Cause
No connection to the
heating circuit PCB (HKK)
No connection to the
auxiliary
PCB (ZPK)
Short circuit, boiler water
temperature sensor
Short circuit, boiler return
temperature sensor
Short circuit, flue gas
temperature sensor
Problem with O sensor
2
Short circuit, outdoor
temperature sensor
Short circuit, top buffer
tank temperature sensor
Troubleshooting
Measures
Check connection

between boiler PCB and
heating circuit PCB.
Notify heating contractor

Check connection

between boiler PCB,
heating circuit PCB and
auxiliary PCB.
Notify heating contractor.

Check boiler water
temperature sensor.
Check boiler return
temperature sensor.
Check flue gas temperature
sensor.
Check the O sensor and
2
calibrate it
Check outdoor temperature
sensor.
Check top buffer tank
temperature sensor.
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