Operating instructions

69
Installation
External hook−up in single boiler systems
Operation with a two−stage burner
Zero volt contacts of the higher
control unit:
Burner stage 1 ON
Burner stage 2 ON
External changeover
of stepped/
modulating burners
External start−up
depending on load
The connections on plugaVD and
aVH are required when connecting
an external hook−up. The cylinder
thermostat is activated when the
cylinder temperature sensor
(accessories) is connected.
Control unit settings
Coding"01:1"
(delivered condition)
The boiler water temperature must
be set to the lower value. The low
temperature boiler is held at the
required minimum temperature.
The high limit safety cut−out settings
and other settings are subject to the
system equipment and the safety
equipment in accordance with
DIN47512.
5862730GB
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