Viessmann VITODENS 200-W Service Instructions Manual page 98

Troubleshooting
Fault codes
(cont.)
Dis- Const.
played
fault
code
C4 X
C5 X
C6
C7 X
C8
Cd X
98
Weath.- System char-
comp. acteristics
X Control mode
X Control mode,
max. pump
speed
X Control mode,
max. pump
speed
X Control mode,
max. pump
speed
X Control mode,
max. pump
speed
X Control mode
Cause Measures
Communica- Check Open
tion error, Therm extension
Open Therm
extension
Communica- Check the setting
tion error, var- of coding address
iable speed "30"
internal pump
Communica- Check setting of
tion error, coding address
external vari- "E5"
able speed
heating circuit
pump, heat-
ing circuit 2
(with mixer)
Communica- Check setting of
tion error, coding address
external vari- "E5"
able speed
heating circuit
pump, heat-
ing circuit 1
(without
mixer)
Communica- Check setting of
tion error, coding address
external vari- "E5"
able speed
heating circuit
pump, heat-
ing circuit 3
(with mixer)
Communica- Check connec-
tion error, tions, Vitocom 100
Vitocom 100 and coding
(KM BUS) address "95"