Heating Curve - Viessmann VITODENS 200-W Operating Instructions For The System User

Terminology
(cont.)
Standard heating mode
For periods when you are at home during the day, heat
your home with the normal room temperature or the
normal flow temperature, depending on the operating
mode. Set the periods (time phases) with the "Stand-
ard" temperature level using the time program for cen-
tral heating.
Room temperature-dependent heating operation
In room temperature-dependent operation a room is
heated until the set room temperature has been
reached. For this, a separate temperature sensor must
be installed in the room.
The heating output is controlled independently of the
outside temperature.
With this operating mode, you can operate one heating
circuit via your control unit. You can input some of the
settings for this heating circuit at your room tempera-
ture controller.
Reduced heating operation
For periods when you will be absent or during the
night, heat your rooms with the reduced room temper-
ature or the reduced flow temperature, depending on
the operating mode. Set the periods (time phases) with
the "Reduced" temperature level using the time pro-
gram for central heating.

Heating curve

Heating curves illustrate the relationship between the
outside temperature, the set room temperature and the
flow temperature. The lower the outside temperature,
the higher the flow temperature.
In order to guarantee sufficient heat with minimum fuel
consumption at any outside temperature, the condi-
tions of your building and system must be taken into
consideration. The heating curve is set by your con-
tractor for this purpose.
Setting the slope and level, taking the heating curve as an example
Factory settings:
■ Slope = 1.4
Level = 0
■
With underfloor heating systems, reduced heating
operation only yields limited energy savings (see
"Underfloor heating system").
Weather-compensated heating operation
In weather-compensated operation, the flow tempera-
ture is controlled according to the outside temperature.
More heat is made available at a lower outside temper-
ature than at a higher one.
The outside temperature is captured and transmitted to
the control unit by a sensor fitted outside the building.
With this operating mode, you can operate several
heating circuits via your control unit. If remote control
units are installed in your rooms, you can also adjust
the settings at the remote control units.
90
80
70
60
50
40
30
20
20 10
Outside temperature in °C
Fig. 5
The heating curves shown apply with the following set-
tings:
Heating curve level = 0
■
Standard room temperature (set room temperature)
■
= 20 °C
Appendix
Heating curve slope
0 -10 -20
1.4
1.2
1.0
0.8
0.6
0.4
0.2
-30
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