Viessmann Vitocrossal 300 CA3 2.5 Installation And Service Instructions Manual page 179

Vitocrossal 300 CA3 Series 2.5 to 6.0 Installation/Service
Boiler System Fault Codes
Displayed System characteristics
fault code
83 If a fault occurs 3 x in 15 min.,
fault is displayed. Burner control
unit goes into a fault state.
88 Burner control unit in a fault state Lead break, boiler water
89 Burner control unit in a fault state Lead break, flue gas temperature
90 Control mode
91 Control mode
92 No solar DHW heating.
93 Control mode.
94 No solar DHW heating.
98 Control mode
99 Control mode
9a No solar DHW heating.
(continued)
Cause
Sensor drift, flue gas temperature
sensor (A or B), burner control unit
temperature sensor, burner
control unit
sensor (A or B), burner control
unit
Short circuit, temperature sensor
/ connection at solar control
module, type SM1.
Short circuit, temperature sensor
aÖ, connection at solar control
module, type SM1.
Short circuit, collector
temperature sensor, connection
of temperature sensor & at solar
control module, type SM1 or
sensor at S1 of the Vitosolic.
Short circuit, temperature sensor,
connection at S3 of the Vitosolic.
Short circuit, DHW tank
temperature sensor, connection
of temperature sensor % at solar
control module, type SM1 or
sensor at S2 of the Vitosolic.
Lead break, temperature sensor
/, connection at solar control
module, type SM1.
Lead break, temperature sensor
aÖ, connection at solar control
module, type SM1.
Lead break, collector temperature
sensor, connection of
temperature sensor & at solar
control module, type SM1 or
sensor at S1 of the Vitosolic.
Troubleshooting
Measures
Check connection cable and
sensors (A and B), replace
sensors if required.
Check connection cable and
dual sensor; replace sensor if
required.
Check connection cable and
sensors (A and B), replace sensor
if required.
Check temperature sensor /
(see separate installation and
service instructions).
Check temperature sensor aÖ
(see separate installation and
service instructions).
Check sensor at the solar control
unit (see separate installation and
service instructions).
Check sensor at the solar control
unit (see separate installation and
service instructions).
Check sensor at the solar control
unit (see separate installation and
service instructions).
Check temperature sensor /
(see separate installation and
service instructions).
Check coding address "20" in
the "Solar" group.
Check temperature sensor aÖ
(see separate installation and
service instructions).
Check coding address "20" in
the "Solar" group.
Check sensor at the solar control
unit (see separate installation and
service instructions).
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