Viessmann VITODENS 333 Service Instructions Manual page 83

Checking and acknowledging faults
Fault code Const.
in the dis-
play
FE X
FF X
Weat- System
h. character-
comp. istics
X Burner
blocked
X Burner
blocked
Troubleshooting
(cont.)
Cause Remedy
Strong interference Remove EMC
(EMC) field nearby; interference.
alternatively boiler If the equip-
coding card or ment will not
main PCB faulty restart, check
the boiler
coding card
and replace,
or replace the
control unit.
Internal error Remove EMC
interference.
If the equip-
ment will not
restart, check
the boiler
coding card
and replace,
or replace the
control unit.
83