Viessmann VITODENS 333 Service Instructions Manual page 93

Repairs
(cont.)
Extension kit for heating circuit with mixer
Checking the rotational direction of the mixer motor
A Rotational direction switch
B ON/OFF switch 8
1. Switch OFF the motor and restart it
at the main ON/OFF switch. The
device will carry out the following
self-test:
&
Mixer close (150 seconds)
&
Pump ON (10 seconds)
&
Mixer open (10 seconds)
&
Mixer close (10 seconds)
Then standard control mode recom-
mences.
2. Note the rotational direction of the
mixer motor during the self-test.
Then set the mixer manually to the
open position.
Note
The flow temperature sensor must
now sense a higher temperature. If
the temperature falls, either the
motor is turning in the wrong direc-
tion or the mixer set is incorrectly
fitted.
Mixer installation instruc-
tions
3. Adjust the rotational direction of the
mixer motor (if required).
&
Switch position I for heating
return from the l.h. side (as deliv-
ered condition).
&
Switch position II for heating
return from the r.h. side.
Troubleshooting
93