Viessmann VITODENS 200-W Installation And Service Instructions Manual page 79

Fault codes
(cont.)
Fault code Const.
displayed
9C X
9E X
9F X
A3
A4
A7
b0 X
b1 X
b5 X
b7 X
b8 X
bA
bb
Weather- System characteris-
comp. tics
X No solar DHW heat-
ing
X Control mode
X Control mode
X Burner blocked
X Control mode
X Control mode as per
delivered condition
X Burner blocked
X Control mode as per
delivered condition
X Control mode as per
delivered condition
X Burner blocked
X Burner blocked
X Mixer regulates to
20 °C flow tempera-
ture.
X Mixer regulates to
20 °C flow tempera-
ture.
Cause Measures
Lead break, cylin- Check temperature sen-
der temperature sor
%
sensor module or sensor on the
Vitosolic.
No flow rate in so- Check solar circuit pump
lar circuit or flow and solar circuit. Acknowl-
rate too low, or edge fault message.
temperature limiter
has responded
Solar control mod- Replace solar control
ule or Vitosolic fault module or Vitosolic
Flue gas tempera- Fit flue gas temperature
ture sensor incor- sensor correctly (see
rectly positioned page 88).
Max. system pres- Check system pressure
sure exceeded max. 3 bar (0.3 MPa)
Check the function and
sizing of the diaphragm
expansion vessel.
Vent the heating system.
Programming unit Replace programming
faulty unit
Short circuit, flue Checking flue gas tem-
gas temperature perature sensor
sensor
Communication er- Checking connections
ror, programming and replacing program-
unit ming unit if required
Internal fault Replacing the control unit
Coding card fault Plug in coding card or re-
place if faulty
Lead break, flue Checking flue gas tem-
gas temperature perature sensor
sensor
Communication er- Check extension kit con-
ror, extension kit nections and code.
for heating circuit 2
(with mixer)
Communication er- Check extension kit con-
ror, extension kit nections and code.
for heating circuit 3
(with mixer)
Troubleshooting
on solar control
79