Viessmann VITODENS 222-F Service Instructions Manual page 71

Vitodens 222-F B2TA 19 and 35 Service
Fault Codes
(continued)
Fault code on display
B0
B1
B5
B7
B8
BA
BB
BC
BD
*1 Control mode: Boiler/burner fully operational (fault code must be verified and reset).
Burner in fault mode: Boiler control requires manual reset before burner can resume operation.
Burner blocked: If fault cause is corrected, burner resumes operation.
System behavior*1
Burner blocked
Control mode (stays in
factory default setting)
Control mode
(factory default setting)
Burner blocked
Burner blocked
Mixing valve regulates to
a supply temperature of
68° F (20° C)
Mixing valve regulates to
a supply temperature of
68° F (20° C)
Control mode without remote
control
Control mode without remote
control
Cause
Flue gas temperature
sensor shorted out
Communication fault;
programming unit
(internal)
Internal fault
Boiler coding card
missing, faulty or
incorrect boiler coding
card
Flue gas temperature
sensor cable broken
Communication fault -
accessory kit for
heating circuit 2 with
mixing valve
Communication error,
extension kit for heating
circuit 3 (with mixing
valve)
Communication error,
remote control Vitotrol
heating circuit 1
(without mixing valve)
Communication error,
remote control Vitotrol
heating circuit 2
(with mixing valve)
Troubleshooting
Corrective action
Check flue gas temperature
sensor (see page 80).
Check connections and
replace programming unit
if required.
Replace the control unit.
Plug in boiler coding card or
replace if faulty.
Check flue gas temperature
sensor (see page 80).
Check extension kit connections
and code.
Check extension kit connections
and code.
Check connections, cable,
coding address "A0" in "Heating
circuit" group and remote
control unit setting.
Check connections, cable,
coding address "A0" in "Heating
circuit" group and remote
control unit setting. For wireless
remote control units: Check
radio path connections, place
remote control unit and wireless
repeater close to the boiler.
Check KM BUS connection to
wireless base station. Replace
wireless components.
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