Viessmann VITODENS 200 Start-Up And Service Instructions page 32

Troubleshooting
Diagnosis
(continued)
Diagnostics table: Faults with fault display on control unit (continued)
Fault message in display window
FAULT: 70
RS WS REMOTE
/
CONTROL
FAULT: 78
RS WS REMOTE
/
CONTROL
FAULT: A1
KM-BUS
BURNER
CONTROL UNIT CONTROL UNIT
FAULT: A2
FAULT: A5
KM-BUS
MIXING VALVE
FAULT: B1
FAULT: B2
FAULT: B3
FAULT: B6
BURNER
CONTROL
UNIT DEFECTIVE
FAULT: CC
*1
(204 )
FAULT: C8
FAULT: C0
FAULT: E4 or E...
FAULT: F2
FAULT: F5
FAULT: F9
*1
(249 )
FAULT: FB
FAULT: FD
*1
(253 )
*1
Displayed when fault codes retrieved from fault memory.
32
Burner fault System behavior
indicator (red)
OFF Operates based on 68 ºF/20 ºC desired daytime
temperature, 58 ºF/14 ºC desired nighttime temperature.
OFF Operates based on 68 ºF/20 ºC desired daytime
temperature, 58 ºF/14 ºC desired nighttime temperature.
Flashes Boiler operates in emergency mode
(after approx. 30 min. BUS fault).
OFF Boiler cools down.
OFF ––
OFF ––
OFF DIP switches A and B on back of are switched
(e.g. A-A or B-B).
OFF Boiler cools down.
OFF Setting via service level not possible.
OFF Boiler cools down.
ON Burner control unit switches to lockout
(due to large line voltage fluctuations).
OFF Boiler does not activate.
OFF Boiler does not activate.
OFF ––
OFF ––
OFF ––
OFF/ON Burner control switches to lockout.
Flashes ––
ON Burner control switches to lockout.