Viessmann FB2B Installation And Service Instructions Manual page 126

Troubleshooting
Repairs
(cont.)
Note the rotational direction of the mixer
motor during its self-test.
Then set the mixer manually to "Open"
again.
Note
The flow temperature sensor must now
capture a higher temperature. If the tem-
perature drops, either the motor is turn-
ing in the wrong direction or the mixer set
is incorrectly fitted.
Mixer installation instructions
Changing the rotational direction of the mixer motor (if required)
gS
|
BU
~
Checking the Vitotronic 200-H (accessories)
The Vitotronic 200-H is connected to the
control unit via the LON cable. To test the
connection, carry out a subscriber check
at the boiler control unit (see page 62).
126
1. Remove the upper casing cover of
the extension kit.
Danger
An electric shock can be life-
threatening.
Before opening the boiler, dis-
connect from the mains volt-
age, for example at the fuse or
the main isolator.
2. At plug gS, swap the cores at termi-
nals "|" and "~".
3. Refit the casing cover.