Fault Codes - Viessmann VITOLIGNO 300-P Service Instructions Manual

Troubleshooting
Fault display

Fault codes

Displayed System characteris-
fault code tics
0F Control mode
10 Regulates as if the
outside temperature
were 0 °C
18 Regulates as if the
outside temperature
were 0 °C
20 Mixer closes
28 Mixer closes
30 Burner blocked
38 Burner blocked
39 Burner blocked
3A Emergency mode,
i.e. the secondary air
damper is put into a
fixed position and will
no longer be regula-
ted.
The system contin-
ues to operate.
40 Mixer closes
88
(cont.)
Cause
Maintenance
Short circuit, out-
side temperature
sensor
Lead break, out-
side temperature
sensor
Short circuit, flow
temperature sen-
sor, heating cir-
cuit 1
Lead break, flow
temperature sen-
sor, heating cir-
cuit 1
Boiler water tem-
perature sensor
faulty
Boiler water tem-
perature sensor
faulty
Flame temperature
sensor faulty
Lead break,
Lambda probe
Short circuit, flow
temperature sen-
sor, heating cir-
cuit 2
Measures
Service the appliance.
After servicing, select
code "24:0".
Check outside tempera-
ture sensor (see
page 98)
Check outside tempera-
ture sensor (see
page 98)
Check flow temperature
sensor (see page 99)
Check flow temperature
sensor (see page 99)
Check boiler water tem-
perature sensor (see
page 96)
Check boiler water tem-
perature sensor (see
page 96)
Check wiring and replace
flame temperature sensor
if required
Check wiring and replace
Lambda probe if required
Check flow temperature
sensor (see page 99)