Viessmann B2UA, Installation And Service Instructions Manual, Page: 148 / 200

148
Checking the solar control module fuse
A
1. Switch off the power. 2. Check fuse A in the solar control
module (see connection and wiring
diagram).
Extension kit, 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.
Heating circuit Rotary se-
lector S1 set-
ting
Heating circuit with mix-
er M2
(Heating circuit 2) 2
2 3 4
5
6
10
9 8 7
Heating circuit with mix-
er M3
(Heating circuit 3) 4
4 2 3
5
6
10
9 8 7
Checking the rotational direction of
the mixer motor
After being switched on, the boiler imple-
ments a self-test. During this, the mixer
is opened and closed again.
Note
The mixer motor can also be started via
the actuator test (see chapter "Checking
outputs").
Troubleshooting
Repair
(cont.)
5773 238 GB