Viessmann Vitodens 050-W Installation And Service Instructions Manual page 73

Fault messages
(cont.)
Displayed fault System characteristics
code
575 Normal operation without
room influence
576 Normal operation without
room influence
577 Normal operation without
room influence
578 Normal operation without
room influence
579 Normal operation without
room influence
682 Burner in a fault state
683 Burner in a fault state
684 Burner in a fault state
694 Burner in a fault state
738 Normal operation
766 Burner output is reduced to
minimum
767 Burner in a fault state
799 No DHW heating, no central
heating
979 Constant heat demand. Set
room temperature is excee-
ded
Cause
Lead break, room temper-
ature sensor, heating cir-
cuit 1
Short circuit, room tem-
perature sensor, heating
circuit 1
Room temperature sen-
sor, heating circuit 2 not
available
Lead break, room temper-
ature sensor, heating cir-
cuit 2
Short circuit, room tem-
perature sensor, heating
circuit 2
Air mass flow rate sensor
not available
Air mass flow rate sensor
faulty
Back draught safety de-
vice faulty
Signal comparison, devia-
tion, flue gas high limit
safety cut-out
OpenTherm remote con-
trol connected but not
configured
Flue gas temperature too
high.
Flue gas temperature too
high.
Central heating circuit
pump reports an electrical
fault. System cannot be
operated as no flow can
be made available.
Both inputs – plug 96 and
OpenTherm – are occu-
pied and reporting a heat
demand
Troubleshooting
Measures
Check external room temperature
sensor for heating circuit or room
temperature sensor on remote
control unit.
Check external room temperature
sensor for heating circuit or room
temperature sensor on remote
control unit.
Check external room temperature
sensor for heating circuit or room
temperature sensor on remote
control unit.
Check setting of parameter 934.6
Check external room temperature
sensor for heating circuit or room
temperature sensor on remote
control unit.
Check external room temperature
sensor for heating circuit or room
temperature sensor on remote
control unit.
Check air mass flow rate sensor.
Check air mass flow rate sensor.
Check back draught safety device.
Check plug-in connection and sen-
sor lead.
Check sensor.
Replace sensor if necessary.
Reset the appliance.
Set C.7 in the commissioning as-
sistant to a value of 14.
Clean the heat cell. Perform main-
tenance.
Clean the heat cell. Perform main-
tenance.
Perform a power reset. If this oc-
curs repeatedly, replace the heat-
ing circuit pump.
Note
Only one input can be used. Either
plug 96 or OpenTherm.
73