Viessmann Vitoligno 300-P Service Instructions For Contractors page 83

Fault display
(cont.)
Fault code System characteris-
on the dis- tics
play
D4 Burner stop initiation,
pellet supply stopped
DA Control mode without
room influence
DB Control mode without
room influence
DD Control mode without
room influence
GB Control mode without
room influence
E0 Control mode
F0 Burner blocked
F1 Burner blocked
Cause
High limit safety
cut-out has
responded (boiler
water temperature
above 100 °C)
Short circuit, room
temperature sen-
sor, heating cir-
cuit 1
Short circuit, room
temperature sen-
sor, heating cir-
cuit 2
Break, room tem-
perature sensor,
heating circuit 1
Break, room tem-
perature sensor,
heating circuit 2
Fault at the LON
user
No connection to
the combustion
controller
Primary air damper
faulty
Troubleshooting
Measures
Wait until the boiler water
temperature has fallen
below the safety tempera-
ture and reset the high
limit safety cut-out
Check the room tempera-
ture sensor (see
page 100)
Check the room tempera-
ture sensor (see
page 100)
Check the room tempera-
ture sensor (see
page 100) and the DIP
switch on the Vitotrol (see
page 94 and 96)
Check the room tempera-
ture sensor (see
page 100) and the DIP
switch on the Vitotrol (see
page 94 and 96)
Check user with the num-
ber 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
83