87
Displayed fault
code
System characteristics
Cause
Measures
F.369
Burner in a fault state
Flame is lost immediately
after flame formation (dur-
ing safety time)
Check gas supply (gas pressure
and gas flow switch).
Check balanced flue system for
flue gas recirculation.
Check ionisation electrode for the
following:
■
Clearance to burner gauze as-
sembly.
■
Contamination on electrode.
Reset the appliance.
F.370
Burner in a fault state
Fuel valve or modulation
valve will not close.
Reset the appliance.
If fault occurs repeatedly, replace
fan unit.
F.372
Burner in a fault state
Repeated flame loss dur-
ing calibration
■
Check ionisation electrode and
connecting cable.
■
Check plug-in connections for
loose contacts.
■
Check flue system. Remove flue
gas recirculation if required.
■
Check system for condensate
backup.
■
Visually inspect gas solenoid
valve inlet and strainer on the in-
let side for contamination.
Note
To prevent water damage, detach
fan unit before removing the burn-
er. Deposits on the electrodes indi-
cate foreign bodies in the combus-
tion 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 ionisation electrode
have been replaced, also clean fan
unit, gas/air channel and Venturi
extension.
Reset the appliance.
F.373
Burner in a fault state
Heat transfer too low dur-
ing calibration
Temperature limiter has
shut down.
■
Ensure adequate heat transfer.
■
Check circulation pump for faults,
scale or blockages.
■
Check 3-way diverter valve func-
tion in actuator test. Vent the sys-
tem.
■
Check function of flow sensor.
Reset the appliance.
Troubleshooting
Fault messages
(cont.)
6151778
Service
