Function Sequence And Possible Faults - Viessmann Vitodens 050-W Installation And Service Instructions Manual

Commissioning, inspection, maintenance

Function sequence and possible faults

Control unit issues a heat
demand
Yes
Fan starts
Yes
Ignition
Yes
Gas solenoid valve opens
Yes
Ionisation current builds
Yes
Burner in operation
Yes
Automatic calibration of
the combustion controller
For further details regarding faults, see chapter "Trou-
bleshooting".
36
Display
No
No
Fault 59, 457
No
Fault 359
No Fault 357
No
Fault 369, 380
No Shuts down below the set
boiler water temperature and
restarts immediately.
Fault 62, 373
No
Fault 346, 377
Measure
Increase set value. Ensure
heat transfer.
Check the fan connecting ca-
bles. Check the fan power
supply.
Check ignition module (con-
trol voltage 230 V across
plug "X1/54" terminals "L"
and "N" on the HBMU).
Check the gas supply.
Check the gas supply pres-
sure.
Check gap between ionisa-
tion electrode and burner
gauze assembly.
Purge the gas line.
Check the flue system for
leaks (flue gas recirculation).
Check gas flow pressure.
Ensure adequate heat trans-
fer. Reset the appliance.
Check gap between ionisa-
tion electrode and burner
gauze assembly.
Check the flue system. Re-
move flue gas recirculation if
necessary.
Reset the appliance.
Operating instructions