Viessmann VITOLIGNO 300-P Service Instructions Manual page 93

Fault display
(cont.)
Displayed System characteris-
fault code tics
DB Control mode without
room influence
DD Control mode without
room influence
DE Control mode without
room influence
E0 Control mode
F0 Burner blocked
F1 Burner blocked
F2 Emergency mode,
i.e. control mode with
max. fan speed
Cause
Short circuit, room
temperature sen-
sor, heating cir-
cuit 2
Lead break, room
temperature sen-
sor, heating cir-
cuit 1
Lead break, room
temperature sen-
sor, heating cir-
cuit 2
Fault at the LON
subscriber
No connection to
the combustion
controller
Primary air damper
faulty
Secondary air
damper faulty
Troubleshooting
Measures
Check the room tempera-
ture sensor (see
page 110)
Check the room tempera-
ture sensor (see
page 110) and the DIP
switch on the Vitotrol (see
pages 107 and 108)
Check the room tempera-
ture sensor (see
page 110) and the DIP
switch on the Vitotrol (see
pages 107 and 108)
Check subscriber against
the number shown on the
display
Check fuse F2 on PCB
A2; check connecting
cable between plug X10
of PCB A1 and plug X24
of PCB A2.
Replace PCB A2 if
required
Replace PCB A1 if
required
Check mechanics, drive
and microswitch. Lift cur-
rent block with d.
Replace faulty parts if
required
Check mechanics, drive
and microswitch and
replace if required.
After the fault has been
removed, it is automati-
cally reset when the boiler
restarts.
93