Viessmann VITODENS 343-F WS4A Installation And Service Instructions Manual page 94

Troubleshooting
Fault codes
(cont.)
Fault code System character-
on the dis- istics
play
9A Control mode
93 Control mode
9b Control mode
94 Control mode
9C Control mode
9F Control mode
A6 Control mode
A7 Control mode as per
delivered condition
b0 Burner blocked
b8 Burner blocked
b1 Control mode as per
delivered condition
94
Cause Measures
Solar: Lead of the Check the sensor (see
collector tempera- page 102).
ture sensor S1 at
the Vitosolic bro-
ken
Solar: Sensor S3 Check the sensor (see
at the Vitosolic page 102).
shorted out
Solar: Lead of the Check the sensor (see
sensor S3 at the page 102).
Vitosolic broken
Solar: Cylinder Check sensor.
temperature sen-
sor S2 at the
Vitosolic shorted
out
Lead of the cylin- Check the sensor (see
der temperature page 102).
sensor S2 at the
Vitosolic broken
Solar control unit See solar control unit
fault message service instructions.
Impressed cur- Check impressed cur-
rent anode faulty; rent anode cable con-
no protective cur- tacts (see page 42)
rent
Faulty program- Replace the program-
ming unit. ming unit.
Flue gas tem- Check the flue gas tem-
perature sensor perature sensor (see
shorted out page 104).
Flue gas tem- Check the flue gas tem-
perature sensor perature sensor (see
lead broken page 104).
Communication Check connections and
fault; program- replace the program-
ming unit (inter- ming unit, if necessary.
nal)