Viessmann VITODENS Operating Instructions Manual page 30

Terminology
Standby mode
Heat generation is switched off.
Setback mode (reduced heating mode)
See "Reduced heating mode".
Constant temperature mode
In constant temperature mode, the heating water is
constantly heated to the selected boiler water tempera-
ture.
Operating program
The operating program determines whether you heat
the rooms and DHW, only heat DHW, or whether you
switch off your heating system and enable frost protec-
tion monitoring.
You can select the following operating programs:
■ " "
The rooms and DHW are heated (winter mode).
■ " "
DHW is provided but there is no central heating
(summer mode).
" "
■
Frost protection for the boiler and DHW cylinder is
active, no central heating, no DHW heating (standby
mode).
Heating circuit
A heating circuit is a sealed unvented circuit that con-
nects the boiler and radiators, in which the heating
water circulates.
Heating circuit pump
Circulation pump for circulating the heating water in
the heating circuit
Actual temperature
Current temperature at the time of the check; e.g.
actual DHW temperature.
Boiler water temperature
See "Constant temperature mode".
30
Only frost protection of heat generator and DHW cylin-
der is active. No central heating, no DHW heating
Note
There is no operating program for central heating with-
out DHW heating. If the rooms are also to be heated,
hot water is generally also required (winter mode).
If you still only want central heating, select the "
operating program and set the DHW temperature to
10 °C: See page 15. This means that you will not heat
DHW unnecessarily but the DHW cylinder is protected
against frost.
"