Viessmann Vitodens 100-W Installation And Service Instructions Manual page 38

Troubleshooting
Fault display
Fault code System character-
displayed istics
10 Continuous opera-
tion
18 Continuous opera-
tion
30 Burner blocked
38 Burner blocked
50 No DHW heating
58 No DHW heating
60 Burner blocked
68 Burner blocked
A9 Control mode with-
out OpenTherm de-
vice
b0 Burner blocked
b8 Burner blocked
E5 Burner blocked
F0 Burner blocked
38
(cont.)
Cause
Short circuit, out-
side temperature
sensor
Lead break, out-
side temperature
sensor
Short circuit, boiler
water temperature
sensor
Lead break, boiler
water temperature
sensor
Cylinder demand
terminal box fault
Cylinder demand
terminal box fault
Short circuit, re-
turn temperature
sensor
Lead break, return
temperature sen-
sor
Communication
error, OpenTherm
device
Short circuit, flue
gas temperature
sensor
Lead break, flue
gas temperature
sensor
Internal fault
Internal fault
Measures
Check the outside tem-
perature sensor and lead
(see page 43).
Check the outside tem-
perature sensor and lead
(see page 43).
Check the boiler water
temperature sensor (see
page 44).
Check the boiler water
temperature sensor (see
page 44).
Check terminal box con-
nections and replace the
terminal box if required.
Check terminal box con-
nections and replace the
terminal box if required.
Check the return temper-
ature sensor (see
page 44).
Check the return temper-
ature sensor (see
page 44).
Check connections and
lead; replace OpenTherm
device if required.
Check sensor (see
page 46).
Check sensor (see
page 46).
Check the ionisation
electrode and connecting
cables.
Press "Reset" (see
page 41).
Replace control unit.