Control Unit - Viessmann VITOLADENS 300-W Installation And Service Instructions Manual

Function description

Control unit

14°C
Boiler temperature
Heating mode
The control unit calculates a set boiler
water temperature depending on the out-
side temperature and/or the room tem-
perature (if a room temperature-control-
led remote control facility is connected)
and the slope/level of the heating curve.
The determined set boiler water temper-
ature is then transferred to the burner
control unit.
DHW heating
The burner, the circulation pump and the
3-way valve are started or changed over
if the cylinder temperature lies 2.5 K
below the set cylinder temperature.
112
HC1
21°C
48°C
The burner control unit calculates the
heat demand and controls the 2-stage
burner accordingly. The boiler water
temperature is limited in the burner con-
trol unit: to 74 °C by the temperature
controller, and to 82 °C by the electronic
temperature limiter. The temperature
limiter in the safety chain locks out the
burner control unit at a boiler water tem-
perature of 100 °C.
In the delivered condition, the set boiler
water temperature is 20 K above the set
cylinder temperature (adjustable via
coding address 60 in group "DHW").
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.