Viessmann Vitocal 300-G Installation And Service Instructions Manual page 73

Electrical connections
X6
F4 F14
aVG
F3 F8 F13
F2 F7 F12
F0 F6 F16
X24
D
X5
X31
A Cross connect PCB
F1 Fuse 6.3 A (slow)
B Extension PCB on main PCB
(cont.)
F20
F3
F18
C
F21
C Main PCB
D Controller and sensor PCB
Installation sequence
X2
A
X1
F1
sYS sYA
sXG sXF sXDsXS
B
F3 Fuse 6.3 A (slow)
X3
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