Viessmann Vitoligno 300-H Installation And Service Instructions For Contractors page 33

Electrical connections
HKK PCB
A1 A2 A3
Fig. 26 HKK PCB
There are 3 connection groups on the HKK PCB:
A1 (Only for one HC)
A2 (For HC or TWE)
A3 (For HC, TWE, SOL or internal electrostatic precipitator)
The connections of a connection group belong
together. The appliances for a specific heating circuit
must be connected to the connections of a group.
(cont.)
A
B
C
For a detailed overview of connection options, see
ZPK 2.03 PCB in chapter "Connection and wiring dia-
gram".
Installation sequence
33