Viessmann VITODENS 200-W Installation And Service Instructions Manual page 68

Troubleshooting
Fault codes
(cont.)
Fault code dis- System characteristics
played
EA Burner in a fault state
68
Cause
Ionisation current too low
during calibration. Differ-
ence compared to previ-
ous value not plausible.
Measures
Check ionisation electrode and
connecting cable. Check plug-in
connections for loose contacts.
Check whether there is a lot of
dust in the ventilation air (e.g. from
construction work).
Check flue system; remove flue
gas recirculation if required.
Check system for condensate
backup.
Note
To prevent water damage, detach
fan unit before removing the burn-
er.
Replace coding card if fault is per-
manent.
Note
Deposits on the electrodes indicate
foreign bodies in the combustion
air. Check the installation room and
flue system for causes of the de-
posits. For example: Laundry de-
tergents, cleaning agents, toilet-
ries, deposits in the ventilation air
supply (chimney).
If burner gauze assembly and ioni-
sation electrode have been re-
placed, also clean fan unit, gas/air
channel and Venturi extension.
Press reset button R.