Viessmann Vitocrossal 300 Series Service Instructions Manual page 87

Vitocrossal 300 CU3A 26 to 199 Service
Fault Codes
(continued)
Fault code on display
9A
9B
DO NOT USE
9C
9E
9F
A7
B0
B1
B5
B7
B8
BA
BB
BC
*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
No solar DHW heating
Control mode
No solar DHW heating
Control mode
Control mode
Control mode (stays in
factory default setting)
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
Cause
Collector temperature
sensor & cable
broken
Tank temperature
sensor cable broken
Tank temperature
sensor % cable
broken
No supply rate in
collector circuit or
flow rate too low or
temperature limiter has
responded
Solar control module
faulty
Faulty programming
unit
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)
Troubleshooting
Corrective action
Check the sensor & at the
solar control module.
Check temperature sensor at
connection S3 to the Vitosolic
solar control.
Check temperature sensor %
on solar control module.
Check solar circuit
pump and solar circuit.
Acknowledge fault message.
Replace solar control module.
Replace the programming unit.
Check flue gas temperature
sensor (see page 95).
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 95).
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.
87