Viessmann Vitoladens 300-W Installation And Service Instructions Manual page 71

Fault codes
(cont.)
Fault code dis- System characteristics
played
b1 Control mode as per deliv-
ered condition
b5 Control mode as per deliv-
ered condition
b7 Burner blocked
b8 Burner blocked
bA Mixer regulates to 20 °C flow
temperature.
bb Mixer regulates to 20 °C flow
temperature.
bC Control mode without remote
control
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
C6 Control mode, max. pump
speed
Cause
Communication error, pro-
gramming unit
Internal fault
Fault, boiler coding card
Lead break, flue gas tem-
perature sensor
Communication error, ex-
tension kit for heating cir-
cuit 2 (with mixer)
Communication error, ex-
tension kit for heating cir-
cuit 3 (with mixer)
Communication error,
Vitotrol remote control,
heating circuit 1 (without
mixer)
Communication error,
Vitotrol remote control,
heating circuit 2 (with mix-
er)
Communication error,
Vitotrol remote control,
heating circuit 3 (with mix-
er)
Incorrect LON communi-
cation module
Communication error, EA1
extension
Communication error, so-
lar control module or
Vitosolic
Communication error,
AM1 extension
Communication fault,
OpenTherm extension
Communication error, in-
ternal variable speed
pump
Communication error, ex-
ternal speed-controlled
heating circuit pump, heat-
ing circuit 2 (with mixer)
Troubleshooting
Measures
Check connections and replace
programming unit if required
Replace the control unit
Plug in boiler coding card or re-
place if faulty
Checking flue gas temperature
sensor
Check extension kit connections
and code.
Check extension kit connections
and code.
Check connections, cable, coding
address "A0" in the "Heating cir-
cuit" group and remote control set-
tings (see page 90).
For wireless remote control units:
check connection; place remote
control close to the boiler.
Check connections, cable, coding
address "A0" in the "Heating cir-
cuit" group and remote control set-
tings (see page 90).
For wireless remote control units:
check connection; place remote
control close to the boiler.
Check connections, cable, coding
address "A0" in the "Heating cir-
cuit" group and remote control set-
tings (see page 90).
For wireless remote control units:
check connection; place remote
control close to the boiler.
Replace LON communication mod-
ule
Check connections
Check solar control module or
Vitosolic
Check connections
Check OpenTherm extension
Check setting for coding address
"30" in the "Boiler" group
Check setting for coding address
"E5" in "Heating circuit" group.
71