Control And Display Elements; Heating Mode - Viessmann VITODENS 333-F WS3A Service Instructions Manual

Constant temperature control unit

Control and display elements

A Pressure gauge
B Fault display (red)
C ON indicator (green)
Keys at the user interface:
O Set boiler water tempera-
ture
F Set DHW temperature
O+F Emissions test function
K Standby mode
L DHW only

Heating mode

The selected set boiler water tem-
perature will be maintained 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 protec-
tion temperature when there is no
demand.
Function description
D Reset button
E User interface
F ON/OFF switch
G Heating and DHW
/ No function
b/a Setting values
d Confirmation
c Information
e Standard settings (Reset)
The boiler water temperature will be
limited:
To 74 °C by the control thermostat
inside the burner control unit.
To 82 °C by the electronic tempera-
ture limiter inside the burner control
unit.
To 100 °C by the temperature limiter
in the safety chain (interlocks the
burner control unit).
91