Viessmann Vitoladens 300-W Service Instructions For Contractors page 78

Function description
Control unit
Control and display elements
A B C D
2
3
1
0 0
4
A Pressure gauge
B Fault indicator (red)
C Optolink interface
only in conjunction with the diagnos-
tic adaptor (accessory) and Vitosoft
(accessory)
Keys at the user interface:
A Central heating time program
B DHW heating and DHW circu-
lation pump time programs (if
connected to the control unit)
H Holiday program
D Time/date
E Reduced room temperature
F Set DHW 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.
78
E
Boiler water temperature
Mo
RESET
F G
°C
+
+
OK
­
D ON indicator (green)
E Reset button
F User interface
G Rotary selector for standard room
temperature
H ON/OFF switch
O+F Emissions test function
K Standby mode
L
DHW only
G Heating and DHW
M Party mode
N
Economy mode
b/a Setting values
d Confirmation
c Information
e Standard settings (Reset)
The burner control unit calculates the
heat demand and controls the two-stage
burner accordingly. The burner control
unit limits the boiler water temperature:
to 74 °C by the temperature controller,
and to 82 °C by the electronic tempera-
ture limiter. The temperature limiter of
the safety chain locks out the burner con-
trol unit at a boiler water temperature of
100 °C.
H