Viessmann VITOCONTROL-S, WB2B, Service Instructions Manual, Page: 78 / 124

78
Fault
code on
the dis-
play Const. weath.-
comp. System char-
acteristics Cause Measures
C6 X Control mode,
max. pump
speed Communica-
tion fault, var-
iable speed
circulation
pump, heat-
ing circuit M2 Check setting of
coding address
"E5"
C7 X X Control mode,
max. pump
speed Communica-
tion fault, var-
iable speed
circulation
pump, heat-
ing circuit A1 Check setting of
coding address
"E5"
Cd X X Control mode Communica-
tion fault
Vitocom 100
(KM BUS) Check connections
and the
Vitocom 100
CE X X Control mode Communica-
tion fault
–
ext. exten-
sion
Check connections
and settings of
coding address
"2E"
CF X Control mode Communica-
tion fault,
LON commu-
nication mod-
ule Replace the LON
communication
module
dA X Control mode
without room
influence Room tem-
perature sen-
sor, heating
circuit A1
shorted out Check the room
temperature sen-
sor, heating circuit
A1
db X Control mode
without room
influence Room tem-
perature sen-
sor, heating
circuit with
mixer M2
shorted out Check the room
temperature sen-
sor, heating circuit
with mixer M2
Troubleshooting
Fault codes
(cont.)
5692 760 GB