Viessmann VITODENS Operating Instructions Manual page 56

Appendix
Terminology
Note
No operating program is available for
central heating without DHW heating.
When you want central heating, hot
water is generally also required (winter
mode).
Operating status
In the operating program "Heating and
DHW", the operating status changes
from "Standard heating mode" to
"Reduced heating mode" and vice versa.
The times for the operating status
changeover are defined by you when
setting the time program.
Extension kit for heating circuit with
mixer
Assembly (accessories) for controlling a
heating circuit with mixer, see "Mixers"
Screed drying
Your heating contractor can,
for example, activate this function for
screed drying in your new build or exten-
sion. This means your screed is dried in
line with a fixed time program (tempera-
ture/time profile) that is appropriate for
the building materials used.
The screed drying function affects heat-
ing circuits with mixer:
■ All rooms are heated according to the
temperature/time profile.
Your settings for central heating have
no effect for the duration of screed dry-
ing (max. 32 days).
■ DHW heating is carried out (but priority
control is cancelled).
56
(cont.)
Underfloor heating
Underfloor heating systems are slow,
low temperature heating systems and
only respond very slowly to short term
temperature changes.
Therefore, heating to the reduced room
temperature at night and enabling
"Economy mode" during short absen-
ces do not result in significant energy
savings.
Heating mode
Standard heating mode
For periods when you will be at home
during the day, heat your rooms to the
standard room temperature. Set the peri-
ods (time phases) using the time pro-
gram for central heating.
Reduced heating mode
For periods when you will be absent or
during the night, heat your rooms to the
reduced room temperature. Set the peri-
ods using the time program for central
heating. With underfloor heating sys-
tems, reduced heating mode only yields
limited energy savings (see "Underfloor
heating system").
Room temperature-dependent heat-
ing mode
In room temperature-dependent mode,
the flow temperature is controlled
according to the room temperature.
More heat is made available at a lower
room temperature than at a higher one.