Viessmann VITODENS 222-F Service Instructions Manual page 83

Vitodens 222-F B2TB 19 and 35 Service
Corrective Action
Heating circuit
Heating circuit with mixing
valve M2 (heating circuit 2) 2
Heating circuit with mixing
valve M3 (heating circuit 3) 4
(continued)
Rotary selector S1 setting
Extension kit for heating circuit with mixing valve
Checking the setting of rotary selector S1:
The rotary selector on the PCB of the extension kit
defines the assignment to the relevant heating circuit.
Note: The rotational direction of the mixing valve motor
during its self-test. Then set the mixing valve
manually to "Open".
Note: The supply temperature sensor must now capture
a higher temperature. If the temperature drops,
either the motor is turning in the wrong direction
or the mixing valve set is incorrectly fitted.
Checking the rotational direction of the mixing valve motor:
After being switched on, the boiler implements a self-test.
During this, the mixing valve is opened and closed again.
Changing the rotational direction of the mixing valve
motor (if required):
1. Remove the upper casing cover of the extension kit.
WARNING
Electric shock hazard indicates an
imminently hazardous situation which,
if not avoided, may result in loss of life,
serious injury or substantial product /
property damage. Before opening the
boiler, disconnect main power.
2. At plug gS, swap the cores at terminals " " and " ".
3. Refit the casing cover.
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
participant check at the boiler control unit (see page 40).
Troubleshooting
83