Viessmann Vitovalor PT2 E11T Installation And Service Instructions Manual page 123

Fault messages for gas condensing module
Fault number System characteristics
on the display
F.463 Burner in a fault state
F.464 Burner in a fault state
(cont.)
Cause
Ionisation current too low
during calibration
Ionisation current too low
during calibration. Differ-
ence compared to previ-
ous value not plausible.
Troubleshooting
Measures
Check the ionisation electrode and
connecting lead (see page 72).
Check plug-in connections for
loose contacts.
Check flue system; remove flue
gas recirculation if required.
Reset burner.
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.
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 burner control unit if fault
is permanent.
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.
Reset burner.
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