99
5790 980 - 04
Vitoligno 300-C Installation/Service
Troubleshooting
Fault Display
(continued)
Fault codes
Fault code displayed
System characteristics
Cause
Measures
49
No values from the external
solar system
The KM-Bus connection to
the vitosolic is broken
Check KM-Bus connection
to the vitosolic
51
No control mode at heating
circuit 1 (KM-BUS)
Short circuit, supply
temperature sensor, heating
circuit 1 (KM-BUS)
Check supply temperature
sensor,
heating circuit 1.
52
No control mode at heating
circuit 2 (KM-BUS)
Short circuit, supply
temperature sensor, heating
circuit 2 (KM-BUS)
Check supply temperature
sensor, heating circuit 2.
53
No control mode at heating
circuit 3 (KM-BUS)
Short circuit, supply
temperature sensor, heating
circuit 3 (KM-BUS)
Check supply temperature
sensor, heating circuit 3.
54
No DHW heating
Short circuit, tank
temperature sensor
Check tank temperature
sensor
55
No flow control
Short circuit, DHW return
temperature sensor
Check return temperature
sensor.
56
No solar yield
Short circuit, collector
temperature sensor
Check collector temperature
sensor.
57
No solar yield
Check collector temperature
sensor.
Check solar reference
sensor.
58
No control mode at heating
circuit 4 (KM-BUS)
Short circuit, supply
temperature sensor
Check supply temperature
sensor.
61
No control mode at heating
circuit 1 (KM-BUS)
Lead break, supply
temperature sensor, heating
circuit 1 (KM-BUS)
Check supply temperature
sensor, heating circuit 1.
62
No control mode at heating
circuit 2 (KM-BUS)
Lead break, supply
temperature sensor, heating
circuit 2 (KM-BUS)
Check supply temperature
sensor, heating circuit 2.
63
No control mode at heating
circuit 3 (KM-BUS)
Lead break, supply
temperature sensor, heating
circuit 3 (KM-BUS)
Check supply temperature
sensor, heating circuit 3.
64
No DHW heating
Lead break, tank
temperature sensor
Check tank temperature
sensor.
65
No flow control
Lead break, DHW return
temperature sensor
Check return temperature
sensor.
66
No solar yield
Lead break, collector
temperature sensor
Check collector temperature
sensor.
67
No solar yield
Lead break, solar reference
sensor
Check solar reference
sensor.
68
No control mode at heating
circuit 4 (KM-BUS)
Lead break, supply
temperature sensor
Check supply temperature
sensor.
8A
Burner blocked
Flue gas temperature in
load operation too low
Check position of ash
box and install correctly if
necessary.