Viessmann VITOTRONIC 100 GC1 Installation And Service Instructions Manual page 20

Heating system types
Circuit Diagram 7
Possible applications
E.g. old systems or systems in market
gardens and/or systems in which there
is no facility for making modifications
or adjustments to the heating circuits
connected downstream.
The cascade and DHW tank control
must be activated by a building
automation system.
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
01: 1 Set coding "01: 3" for multi-boiler system
with external cascade control via switch
contacts
02: 1 Set coding "02: 2" for operation with
modulating burner
03: 0 Set coding "03: 1" for oil-fired operation
(re-setting is not possible)
0C: 4 Set coding "0C: 1" for continuous return
temperature control
4A: 0
4d: 1 Set coding "4d: 2" for boiler circuit pump
at plug sL
20
(continued)
When the return temperature falls
below the required minimum value,
the 3-port mixing valve on the boilers
is proportionally closed via the
temperature sensor T1, thereby
assuring protection of the boiler.
The boiler and the heating circuits
downstream are hydraulically
decoupled. The supply temperature
is controlled via the common
temperature sensor.
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Automatic change
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Connection of the temperature sensor T1 at
plug aJA;
Coding is automatically changed to "4A: 1"
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