Viessmann VITODENS 111-W Installation And Service Instructions Manual page 44

Troubleshooting
Fault messages on the display
Displayed System characteris-
fault code tics
51 No DHW heating
58 No DHW heating
59 No DHW heating
A9 Control mode without
OpenTherm device
b0 Burner blocked
b8 Burner blocked
E3 Burner in a fault
state
E5 Burner blocked
F0 Burner blocked
F1 Burner in a fault
state
44
(cont.)
Cause
Short circuit, outlet
temperature sen-
sor
Lead break, cylin-
der temperature
sensor
Lead break, outlet
temperature sen-
sor
Communication
error, OpenTherm
device
Short circuit, flue
gas temperature
sensor
Lead break, flue
gas temperature
sensor
Fault in safety
chain.
Internal fault
Internal fault
Max. flue gas tem-
perature exceeded
Measures
Check the sensor (see
page 51).
Check the sensor (see
page 50).
Check the sensor (see
page 51).
Check connections and
cable; replace Open-
Therm device if required.
Check the sensor (see
page 53).
Check the sensor (see
page 53).
Check the temperature
limiter and connecting
leads (see page 52).
Check the control unit,
and replace if required.
Check the ionisation elec-
trode and connecting
cables.
Press "RESET" (see
page 46).
Replace control unit.
Check heating system fill
level. Check circulation
pump. Vent the system.
Press "RESET" (see
page 46).