Viessmann VITODENS 200-W Service Instructions Manual page 99

Fault codes
(cont.)
Dis- Const. Weath.-
played comp.
fault
code
98 X X
99 X X
9A X X
9b X X
9C X X
9E X X
9F X X
A6 X X
A7 X
System char- Cause
acteristics
Control mode Lead broken,
temperature
sensor /
Control mode Lead broken,
temperature
sensor aÖ
No DHW heat- Lead break,
ing collector tem-
perature sen-
sor
Control mode Lead break,
cylinder tem-
perature sen-
sor
No DHW heat- Lead break,
ing cylinder tem-
perature sen-
sor
Control mode No flow rate
in the collec-
tor circuit or
flow rate too
low, or tem-
perature lim-
iter has
responded
Control mode Solar control
module or
Vitosolic
faulty
Control mode Impressed
current anode
faulty
Control mode Programming
as per deliv- unit faulty
ered condition
Troubleshooting
Measures
Check sensor /
on the solar control
module
Check sensor aÖ
on the solar control
module
Check temperature
sensor & on the
solar control mod-
ule or the Vitosolic
sensor
Check temperature
sensor at connec-
tion S3 to the
Vitosolic 100
Check temperature
sensor % on the
solar control mod-
ule or the Vitosolic
sensor
Check solar circuit
pump and solar cir-
cuit. Acknowledge
fault message
Replace solar con-
trol module or
Vitosolic
Replace
impressed current
anode
Replace program-
ming unit
99