Viessmann VITODENS 100-W Installation And Service Instructions Manual page 35

Fault messages on the display
Displayed System characteris-
fault code tics
FC Burner blocked
Fd Burner blocked
FF Burner blocked
(cont.)
Cause
Electrical fan con-
trol (control unit)
faulty
Fault, burner con-
trol unit
Fault, burner con-
trol unit
Troubleshooting
Measures
Check fan connecting ca-
ble; if required, replace or
replace control unit.
Check ignition electrodes
and connecting cables.
Check whether a strong
interference (EMC) field
exists near the appliance.
Press "Reset" (see
page 36).
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" (see
page 36).
Replace control unit if
fault persists.
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