Viessmann Vitodens 050-W Installation And Service Instructions Manual page 62

Troubleshooting
Fault messages
(cont.)
Displayed fault System characteristics
code
184 Burner in a fault state
299 Date/time wrong
346 Burner in a fault state
347 Burner in a fault state
348 Burner in a fault state
349 Burner in a fault state
350, 351 Burner in a fault state
62
Cause
Short circuit, flow temper-
ature sensor/high limit
safety cut-out
Real-time clock fault
Ionisation current calibra-
tion error
Flue gas recirculation
Gas modulation valve
Air mass rate flow not de-
tected correctly in fan unit.
Ionisation current lies out-
side the permissible range
Measures
Check the flow temperature sen-
sor/high limit safety cut-out.
Check sensor lead. Replace faulty
component if necessary.
Reset the appliance.
Check time and date and set if
necessary.
Check the gas supply pressure.
■
Check gas solenoid valve inlet
■
strainer for contamination.
Check ionisation electrode for
■
contamination.
Check the flue system. Remove
■
flue gas recirculation if necessa-
ry.
Check the condensate drain
■
(condensate backup).
Reset the appliance.
Remove flue gas recirculation.
Check entire flue gas path for the
following:
Flue gas back pressure caused
■
by water pocket (if flue system
fall is insufficient), constriction,
blockage.
Repair flue system if necessary.
■
Reset the appliance.
If several heat generators are con-
nected to a common flue system:
Check whether "Multiple connec-
tion" is set in the commissioning
assistant.
Check the flue system for unre-
stricted flow.
If fault remains, replace gas fan
unit.
Check for dust contamination in
■
the ventilation air.
Check burner gauze assembly
■
for contamination.
Reset the appliance. If the fault oc-
curs repeatedly, replace the gas
fan unit.
Replace the HBMU heat manage-
ment unit. See chapter "Replacing
the HBMU heat management unit".