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Vitocrossal 300 CU3A 26 to 199 Service
5673 649 - 18
86
Troubleshooting
Fault Codes
(continued)
Fault code on display
System behavior
*1
Cause
Corrective action
10
Boiler operates based on outdoor
temperature of 32°F (0°C)
Short circuit on outdoor
temperature sensor
Check the outdoor temperature
sensor (see page 93).
18
Boiler operates based on outdoor
temperature of 32°F (0°C)
Outdoor temperature
sensor cable broken
Check the outdoor temperature
sensor (see page 93).
30
Burner blocked
Short circuit on boiler
water temperature
sensor
Check the boiler water
temperature sensor
(see page 94).
38
Burner blocked
Boiler water temperature
sensor cable broken
Check the boiler water
temperature sensor
(see page 94).
40
Mixing valve closes
Heating circuit 2 with
mixing valve supply
short circuit on
temperature sensor
Check the supply
temperature sensor
(see page 94).
44
Mixing valve closes
Short circuit, supply
temperature sensor,
heating circuit 3
(with mixing valve)
Check supply temperature
sensor (see page 94).
48
Mixing valve closes
Heating circuit 2 with
mixing valve supply
temperature sensor
cable broken
Check the supply temperature
sensor (see page 94).
4C
Mixing valve closes
Supply temperature
sensor cable broken
circuit 3 (with mixing
valve)
Check supply temperature
sensor (see page 94).
50
No DHW heating
Short circuit on DHW
tank temperature sensor
Check the DHW sensor
(see page 94).
58
No DHW heating
Tank temperature
sensor cable broken
Check the sensor (see page 94).
90
Control mode
Short circuit,
temperature sensor
/
Check sensor
/
on solar
control module
91
Control mode
Short circuit,
temperature sensor
aÖ
Check sensor
aÖ
on solar
control module
92
No solar DHW heating
Short circuit, collector
temperature sensor
Check temperature sensor
&
on solar control module or
Vitosolic sensor
93
Control mode
Short circuit, tank
temperature sensor
Check temperature sensor at
connection S3 to Vitosolic 100
94
No solar DHW heating
Short circuit, tank
temperature sensor
Check temperature sensor
%
on
solar control module or Vitosolic
sensor
98
Control mode
Lead break, temperature
sensor
/
Check sensor
/
on solar
control module
99
Control mode
Lead break, temperature
sensor
aÖ
Check sensor
aÖ
on solar
control module
*1
Control mode:..............Boiler/burner fully operational (fault code must be verified and reset).
Burner in fault mode:.....Boiler control requires manual reset before burner can resume operation.
Burner blocked: ...........If fault cause is corrected, burner resumes operation.