Viessmann Vitodens 200 Service Instructions Manual page 71

Fault codes
(cont.)
Display Const. Weath.-
fault comp.
code
9F X X
A7 X
b0 X X
b1 X X
b4 X X
b5 X X
b7 X X
b8 X X
System char- Cause
acteristics
Control mode Solar control
unit fault;
displayed if a
fault without
fault code
occurs at the
solar control
unit
Control mode Faulty pro-
as per the de- gramming
livered condi- unit
tion
Burner Flue gas
blocked temperature
sensor
shorted out
Control mode Communica-
as per the de- tion error;
livered condi- program-
tion ming unit (in-
ternal)
Regulates as Internal fault
if the outside
temperature
was 0 °C
Control mode Internal fault
as per the de-
livered condi-
tion
Burner Boiler coding
blocked card miss-
ing, faulty or
incorrect
boiler coding
card
Burner Flue gas
blocked temperature
sensor lead
broken
Troubleshooting
Measures
Check the solar
control unit (see
solar control unit
service instruc-
tions).
Replace the pro-
gramming unit.
Check the flue
gas temperature
sensor (see page
80).
Check connec-
tions and replace
the programming
unit if required.
Replace the con-
trol unit.
Replace the con-
trol unit.
Plug in boiler cod-
ing card or re-
place it, if faulty.
Check the flue
gas temperature
sensor (see page
80).
71