Viessmann VITODENS 200-W WB2B Service Instructions For Contractors page 71

Fault codes
(cont.)
Fault Const. Weath.-
code comp.
on the
display
28 X
30 X X
38 X X
40 X
48 X
50 X X
58 X X
System char- Cause
acteristics
Regulates System flow
without flow temperature
temperature sensor lead
sensor (low broken
loss header)
Burner Boiler water
blocked temperature
sensor
shorted out
Burner Boiler water
blocked temperature
sensor lead
broken
Mixer closes Heating cir-
cuit with
mixer M2
flow tem-
perature
sensor
shorted out
Mixer closes Heating cir-
cuit M2 flow
temperature
sensor lead
broken
No DHW heat- Cylinder
ing temperature
sensor
shorted out
No DHW heat- Cylinder
ing temperature
sensor lead
broken
Troubleshooting
Measures
Check the low
loss header sen-
sor (see page 82).
Check the boiler
water tempera-
ture sensor (see
page 82).
Check the boiler
water tempera-
ture sensor (see
page 82).
Check the flow
temperature sen-
sor.
Check the flow
temperature sen-
sor.
Check the sensor
(see page 82).
Check the sensor
(see page 82).
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