Viessmann VITODENS 100-W Installation And Service Instructions Manual page 68

Troubleshooting
Fault finding
(cont.)
Display System character-
fault code istics
0b Burner blocked
0C Burner blocked
30 Burner blocked
38 Burner blocked
51 No DHW heating
59 No DHW heating
b1 Control mode
b5 Control mode
E4 Burner blocked
E5 Burner blocked
E6 Burner blocked
F0 Burner blocked
F2 Burner in fault state
68
Cause Measures
Flow of water to Check the circulation
low. pump.
Air in heat ex- Vent the heating sys-
changer. tem.
Flow switch Check the interconnect-
faulty. ing cable.
Voltage to low. Contact the electricity
supplier.
Boiler tempera- Check the boiler tem-
ture sensor perature sensor (see
shorted out page 72).
Boiler tempera- Check the boiler tem-
ture sensor lead perature sensor (see
break page 72).
Draw off tempera- Check sensors (see
ture sensor short page 74).
circuit
Draw off tempera- Check sensors (see
ture sensor short page 74).
circuit
Communication Check connections and
fault program- replace the program-
ming unit (inter- ming unit, if necessary.
nal)
Internal fault Replace control unit.
Fault supply Replace control unit.
voltage
Internal fault Check the ionisation
electrode and leads.
Press"Reset".
Water pressure Top up water (see
too low page 63).
Internal fault Replace control unit.
Temperature limit- Check the heating sys-
er has responded tem water level. Check
the circulation pump.
Vent the heating sys-
tem. Check the tem-
perature limiter and
leads.
Press"Reset".