Constant Temperature Control Unit; Heating Mode; Dhw Heating; Weather-Compensated Control Unit - Viessmann Vitodens 200-W Series Installation And Service Instructions Manual

Constant temperature control unit

4 8
s
Fig. 55

Heating mode

The selected set boiler water temperature will be main-
tained when a demand is being raised by the room
thermostat and the heating program is set to DHW and
central heating " ".
G
The boiler water temperature will be maintained at the
default frost protection temperature when there is no
demand.

DHW heating

The burner and the circulation pump for cylinder heat-
ing are started if the cylinder temperature lies 2.5 K
below the set cylinder temperature.

Weather-compensated control unit

21°C
14°C
Boiler temperature 48 °C
Fig. 56
Heating mode
The control unit determines a set boiler water tempera-
ture subject to outside temperature or room tempera-
ture (if a room temperature-dependent remote control
is connected) and to the slope
curve.
°C
A
HC1
level of the heating
/
The electronic temperature limiter inside the burner
control unit limits the boiler water temperature.
Flow temperature setting range: 20 to 74 °C.
In the delivered condition, the set boiler water temper-
ature is 20 K higher than the set DHW temperature
(adjustable via coding address "60"). The burner will
be switched off and the circulation pump run-on time
will begin, if the actual cylinder temperature exceeds
the set cylinder temperature by 2.5 K.
The determined set boiler water temperature is trans-
ferred to the burner control unit. From the set and
actual boiler water temperatures, the burner control
unit calculates the modulation level and regulates the
burner accordingly.
Function description
91