Viessmann VITODENS 333-F WS3A Service Instructions Manual page 81

Fault codes
(cont.)
Fault Const. Weath.-
code comp.
on the
display
F9 X X
FA X X
Fd X X
FE X X
FF X X
System char- Cause
acteristics
Burner in a Fan speed
fault state too low dur-
ing burner
start
Burner in a Fan not at
fault state standstill
Burner Fault at the
blocked burner con-
trol unit
Burner Strong inter-
blocked or in a ference
fault state (EMC) field
nearby, or
faulty main
PCB
Burner Strong inter-
blocked or in a ference
fault state (EMC) field
nearby, or in-
ternal fault
Troubleshooting
Measures
Check the fan, fan
connecting
cables, fan power
supply and con-
trol; press "E"
Check the fan, fan
connecting cables
and fan control;
press "E"
Check the ignition
electrodes and
connecting
cables/leads;
check for any
strong interfer-
ence (EMC) field
near the equip-
ment; press "E".
Replace the con-
trol unit if the fault
persists
Start the equip-
ment again. Re-
place the control
unit if the equip-
ment will not re-
start.
Start the equip-
ment again. Re-
place the control
unit if the equip-
ment will not re-
start.
81