Viessmann VITOTRONIC 100 GC1 Installation And Service Instructions Manual page 26

Heating system types
Circuit Diagram 10
Possible applications
For heating circuits with different
temperatures.
IMPORTANT
This circuit diagram represents a
recommendation only. It is the
responsibility of the customer and/or
heating contractor to check that this
recommendation is complete and fully
functional. Three-phase equipment
must be connected via additional
power contactors.
Available system accessories
Flue gas temperature sensor
Coding of Change required
system type
00: 1
02: 1 Set coding "02: 2" for operation with
modulating burner
0C: 4 Set coding "0C: 0"
0d: 2 Set coding "0d: 0"
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(continued)
The Vitocrossal 300 is operated with
constant boiler water temperature by
means of the boiler control unit.
Two-stage or modulating burners can
be controlled.
The Vitocrossal 300 has two return
connections. The heating circuits with
the higher return temperature are
connected to the return connection at
the top, those with the lower
temperatures to the return connection
at the bottom.
Please note:
At least 15% of the take-off from the
rated output must be connected to the
return connection at the bottom.
The boiler water temperature which is
established in the heating mode is
higher than the maximum heating
circuit supply temperature by an
adjustable difference.
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Automatic change
With DHW tank:
Coding is automatically changed to "00: 2"
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