Bcu Burner Control Unit - Viessmann VITODENS 222-F Installation And Service Instructions Manual

BCU burner control unit

Fig. 68
PWM Control signal
X... Electrical interfaces
§ A/B Flow temperature sensors 1 and 2
Outlet temperature sensor
$
Ionisation electrode
aA
Flue gas temperature sensor
aG
sÖ Internal circulation pump (primary pump)
3-way diverter valve
dÖ
Gas solenoid valve
dG
B
Connection and wiring diagram
A
Power supply
fÖ
gF Ignition unit
Fan motor
a-Ö
A Fan motor control
a-Ö
Water pressure sensor
aND
A Water pressure sensor
aND
BCU burner control unit
A
HMU heat management unit (plug
B
HMU heat management unit (plug X4)
C
C
)
aBH
107