Viessmann VITODENS Operating Instructions Manual page 59

Terminology
Factory settings: Slope = 1.4 and level
= 0.
110
+20
Outside temperature in °C
A Changing the slope:
The steepness of the heating curve
changes.
B Changing the level:
The heating curves are shifted in
parallel in a vertical direction.
Heating circuit
A heating circuit is a sealed unvented
circuit between the boiler and radiators,
in which the heating water circulates.
A heating system may comprise several
heating circuits. For example, one heat-
ing circuit for the rooms occupied by you
and one heating circuit for the rooms of
a separate apartment.
Heating circuit pump
Circulation pump for the circulation of the
heating water in the heating circuit
(cont.)
3.5
1.4
A
B
0.2
-20
Mixer
Hot heating water from the boiler is
mixed with cooled heating water from the
heating circuit. The heating water,
brought to the right temperature as
required, is pumped to the heating circuit
by the heating circuit pump. The control
unit adjusts the flow temperature via the
mixer to suit different conditions, e.g.
changing outside temperatures.
Night setback
See "Reduced heating mode"
Open flue operation
The combustion air is drawn from the
room where the boiler is installed.
Balanced flue operation
The combustion air is drawn from out-
side the building.
Room temperature
■ Standard room temperature:
For periods when you will be at home
during the day, set the standard room
temperature.
■ Reduced room temperature:
For periods when you will be absent or
during the night, set the reduced room
temperature; see "Heating mode".
Appendix
59