Viessmann VITODENS 222-F Service Instructions Manual page 76

Troubleshooting
Fault Codes
(continued)
Fault code on display
FA
FC
FD
FE
FF
*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.
76
System behavior*1
Burner in fault mode
Burner in fault mode
Burner in a fault state and
additional fault B7 is displayed
Burner in a fault state
Burner in fault mode
Burner in fault mode
Vitodens 222-F B2TA 19 and 35 Service
Cause
Fan not at standstill
Gas valve faulty or faulty
modulation valve control;
or vent system blocked
Boiler coding card is
missing
Fault, burner control
unit
Damaged or incorrect
boiler coding card or
main PCB
Internal fault or reset
button R blocked
Corrective action
Check the fan, the fan
connecting cables and fan
control. Check the fan control.
Press reset button R.
Check the gas valve.
Check the vent system.
Press reset button R.
Insert the boiler coding card.
Press reset button R.
Replace control unit if fault
persists.
Check ignition electrodes and
connecting cables. Check
whether a strong interference
(EMC) field exists near the
appliance. Press reset button R.
Replace control unit if fault
persists.
Press reset button R. If the fault
persists, check the boiler coding
card or replace it or the control
unit.
Restart the equipment.
Replace the control unit if the
equipment will not restart.