Viessmann Vitotronic 200 Installation And Service Instructions Manual page 10

Preparing for installation
System version 4
Single boiler system with Vitocrossal 300, optionally with
one low temperature heating circuit
Note
The heating circuits with the higher return temperature are connected to the
upper return connector and those with lower return temperatures to the lower
return connector.
For systems without low temperature heating circuit, always connect to the
lower return connector.
Connect at least 15 % of the rated output to the lower return connector.
A Boiler with Vitotronic 200 with
LON communication module
B DHW cylinder
C Vitotronic 200-H with
LON communication module
D Mixer circuit
10
E Low temperature heating circuit
or
F Underfloor heating circuit
G Temperature limiter (maximum
limit)