Viessmann VITODENS 242-F Installation And Service Instructions Manual page 131

Fault codes
(cont.)
Displayed System characteris-
fault code tics
CF Control mode
No communication
via LON.
d6 Control mode
d7 Control mode
d8 Control mode
dA Control mode without
room influence
db Control mode without
room influence
dC Control mode without
room influence
dd Control mode without
room influence
dE Control mode without
room influence
dF Control mode without
room influence
Cause
Communication er-
ror, LON communi-
cation module
Input DE1 reports a
fault at extension
EA1
Input DE2 at exten-
sion EA1 reports a
fault
Input DE3 at exten-
sion EA1 reports a
fault
Short circuit, room
temperature sen-
sor, heating circuit
1 (without mixer)
Short circuit, room
temperature sen-
sor, heating circuit
2 (with mixer)
Short circuit, room
temperature sen-
sor, heating circuit
3 (with mixer)
Lead break, room
temperature sen-
sor, heating circuit
1 (without mixer)
Lead break, room
temperature sen-
sor, heating circuit
2 (with mixer)
Lead break, room
temperature sen-
sor, heating circuit
3 (with mixer)
Troubleshooting
Measures
Check LON communica-
tion module and replace if
required.
If no LON communication
module is installed, set
code "76:0" in the "Gen-
eral" group.
Remove fault at appliance
concerned
Remove fault at appliance
concerned
Remove fault at appliance
concerned
Check room temperature
sensor, heating circuit 1
Check room temperature
sensor, heating circuit 2
Check room temperature
sensor, heating circuit 3
Check room temperature
sensor for heating circuit 1
and remote control config-
uration (see page 168)
Check room temperature
sensor for heating circuit 2
and remote control config-
uration (see page 168)
Check room temperature
sensor for heating circuit 3
and remote control config-
uration (see page 168)
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