Opening The Vitotronic 300; General Information - Viessmann Vitotronic 300 Series Operating Instructions Manual

Operation - General
Vitotronic 300, GW6B Operating

Opening the Vitotronic 300

The programming unit is located behind cover flap A.
To open, pull the top edge of the hinged cover forward.

General Information

Each boiler is equipped with its own control unit.
In a multi boiler system only one control unit takes on the
function of boiler and heating circuit control unit and that
of the higher weather-compensated cascade control unit.
This is referred to in the following as the Cascade control
unit.
The display shows "Lead boiler + cascade".
The other control units take on the function of a boiler
control unit for constant temperature operation. This is
referred to in the following as the Lag boiler control unit.
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