Viessmann VITODENS 222-F Installation And Service Instructions Manual page 87

Fault messages
(cont.)
Fault number System characteristics
on the display
F.468 Burner in a fault state
F.471 No heat demand
F.473 No heat demand
F.474 Burner in a fault state
F.517 Control mode, remote control
unit not functioning
F.527 Burner locked out
F.528 Burner locked out
F.540 Burner in a fault state
F.542 Mixer closes. Heating circuit
pump is operational.
Cause
Ionisation current too high
during calibration
System pressure sensor
not available
HMU heat management
unit communication error
Error in scheduled pro-
gram run monitoring
Communication error
wired remote control
Vitotrol
Update parameters faulty
or incomplete
Basic programming faulty
or incomplete
Condensate backup in the
heat cell
Lead break, flow tempera-
ture sensor, heating circuit
1 with mixer
Troubleshooting
Measures
Check gap between ionisation
electrode and burner gauze as-
sembly.
Heat generator installation
and service instructions
Check whether there is a lot of
dust in the ventilation air (e.g. from
construction work).
Note
Deposits on the electrodes indicate
foreign bodies in the ventilation 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 the appliance.
Check the system pressure sensor.
Check connecting cable between
burner control unit and HMU heat
management unit.
Reset the appliance.
Check remote control unit connect-
ing cable and setting.
Repeat BCU burner control unit
flash operation.
Repeat BCU burner control unit
flash operation.
Check system for condensate
backup.
Check the condensate drain and
trap.
Note
To prevent water damage, detach
fan unit before removing the burn-
er.
Reset the appliance.
Check flow temperature sensor
TS1 on extension kit mixer (ADIO
electronics module). See
page 91.
87