Viessmann VITOLADENS 300-W Installation And Service Instructions Manual page 99

Fault codes
(cont.)
Displayed System characteris-
fault code tics
bd Control mode without
remote control
bE Control mode without
remote control
bF Control mode
C1 Control mode
C2 Control mode
C3 Control mode
C4 Control mode
C5 Control mode, max.
pump speed
Cause
Communication er-
ror, remote control
Vitotrol heating cir-
cuit 2 (with mixer)
Communication er-
ror, remote control
Vitotrol heating cir-
cuit 3 (with mixer)
Incorrect LON
communication
module
Communication er-
ror, extension EA1
Communication er-
ror, solar control
module or
Vitosolic
Communication er-
ror, extension AM1
Communication er-
ror, OpenTherm
extension
Communication er-
ror, variable speed
internal pump
Troubleshooting
Measures
Check connections, ca-
ble, coding address "A0"
in "Heating circuit"
group and remote control
settings (see page 127).
For wireless remote con-
trols: Check connections,
place remote control unit
close to the boiler
Check connections, ca-
ble, coding address "A0"
in "Heating circuit"
group and remote control
settings (see page 127).
For wireless remote con-
trols: Check connections,
place remote control unit
close to the boiler
Replace LON communi-
cation module
Checking connections
Check solar control mod-
ule or Vitosolic
Checking connections
Check OpenTherm exten-
sion
Check coding address
setting "30" in "Boiler"
group.
99