Viessmann VITODENS 200-W Installation And Service Instructions Manual page 104

Troubleshooting
Fault messages
(cont.)
Displayed fault System characteristics
code
E8 Burner in a fault state
E9 Burner in a fault state
104
Cause
Ionisation current lies out-
side the permissible range
Repeated flame loss dur-
ing calibration
Measures
Check gas supply (gas pressure
and gas flow switch), gas train and
connecting cable.
Check assignment of gas type (see
page 34).
Check ionisation electrode for the
following:
Distance to burner gauze assem-
■
bly (see page 44)
Contamination on electrode
■
Press reset button R.
Check the ionisation electrode and
connecting lead (see page 44).
Check plug-in connections for
loose contacts.
Check flue system; remove flue
gas recirculation if required.
Check system for condensate
backup.
Visually inspect gas train inlet and
strainer on the inlet side for con-
tamination.
Note
To prevent water damage, detach
fan unit before removing the burn-
er.
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.