Viessmann VITOTRONIC 100 Operating Instructions Manual page 53

Terminology
The screed function affects the heating
circuits with a mixer:
■ All rooms are heated according to the
temperature/time profile.
Your settings for central heating have
no effect for the duration of the building
drying.
■ DHW heating is carried out (but priority
control is cancelled).
Heating program
The heating program determines
whether you heat your rooms and DHW,
or only heat DHW, or whether you shut
down your heating system with frost pro-
tection monitoring.
You can select the following heating pro-
grams:
■ "Heating and DHW"
The rooms are heated and DHW is
provided (winter mode).
■ "Only DHW"
DHW is provided but there is no cen-
tral heating (summer mode).
■ "Standby mode"
Frost protection for the boiler and the
DHW cylinder is enabled, no central
heating, no DHW heating.
Note
No heating program is available for cen-
tral heating without DHW heating. When
you want central heating, hot water is
generally also required (winter mode).
If you do want just central heating, select
the heating program "Heating and
DHW" and set the DHW temperature to
10 °C (see chapter "Setting the DHW
temperature"). This means that you will
not heat DHW unnecessarily but the
DHW cylinder is protected against frost.
(cont.)
Operating status
In the heating program "Heating and
DHW", the operating status changes
from "Standard heating mode" (see
page 55) to the operating status
"Reduced heating mode" (see
page 56) and vice versa. The times for
the operating status change are defined
when the time program is set.
Extension kit for heating circuit with
mixer
Assembly (accessory) for controlling a
heating circuit with mixer.
See "Mixer".
Heating curve
Heating curves illustrate the relationship
between the outside temperature, room
temperature (set value) and boiler water
or (heating circuit) flow temperature. The
lower the outside temperature, the
higher the boiler water temperature or
heating circuit flow temperature.
In order to guarantee sufficient heat and
minimum fuel consumption at any out-
side temperature, the conditions of your
building and your heating system must
be taken into consideration. The heating
curve is set by your heating contractor
for this purpose.
Note
If your heating system includes heating
circuits with mixers, then the flow tem-
perature for the heating circuit without
mixer is higher by a selected differential
than the flow temperature for the heating
circuits with mixer.
Appendix
53