Viessmann Vitodens 222-F B2TA Installation And Service Instructions Manual page 146

Troubleshooting
Repair
(cont.)
Checking the fuse
A
1. Switch off the power.
2. Release the side closures and pivot
the control unit down.
Extension kit for heating circuit with mixer
Checking the setting of rotary selec-
tor S1
The rotary selector on the PCB of the
extension kit defines the assignment to
the relevant heating circuit.
146
F1
3. Remove cover A.
4. Check fuse F1 (see connection and
wiring diagram).
Heating circuit
Heating circuit with mix-
er M2
(heating circuit 2)
Heating circuit with mix-
er M3
(heating circuit 3)
Rotary se-
lector S1 set-
ting
2
4