Datasheet

5822 239 GB
46
3.3 Installation notes
Connection to the external changeover facility
The connection is made on site via
terminals ”1” and ”2” of the plug-in
connector aVH.
H
to Vitotronic 100 (type GC1) in conjunction with Vitotronic 333 (type MW1)
Volt-free contacts:
Block boiler
Start boiler as the last one in the boiler
sequence
Block boiler
Connect the volt-free contact at
terminals ”1” and ”2” of plug aVD.
Contact closed:
The boiler is blocked.
It is taken out of the boiler sequence, i.e.
the butterfly valve or the 3-way mixing
valve is closed for constant return
temperature control and the shunt or
boiler circuit pumps are switched off. The
other boilers must provide the required
heating.
Please note:
The heating s ystem is no longer
protected against frost if all boilers are
blocked or there are no other available
boilers.
Contact open:
The boiler is reinstated into the current
boiler sequence.
Start boiler as the last one in the boiler
sequence
Connect the volt-free contact at
terminals ”2” and ”3” of plug aVD.
Contact closed:
The boiler is started as the last one in the
boiler sequence.
The heat demand of the heating system is
being met by the other boilers. This boiler
is started if the other boilers do not
provide sufficient heat.
Contact open:
The boiler is reinstated into the current
boiler sequence.
External request
External blocking/close mixer
External heating program changeover/
open mixer
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