Function Description; Constant Temperature Control Unit - Viessmann VITODENS 200-W Service Instructions Manual

Constant temperature control unit

s
Heating mode
The selected set boiler water tempera-
ture 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 protection
temperature when there is no demand.
DHW heating with gas fired combi boilers
If the flow switch detects that hot water
is being extracted (> 3 l/min) then the
burner, circulation pump and 3-way
valve are switched on or changed over.
The burner modulates according to the
DHW outlet temperature and is limited by
the temperature limiter (82 °C) on the
boiler side.
DHW heating with a gas fired boiler
The burner, the circulation pump and the
three-way valve are started or changed
over if the cylinder temperature lies 2.5
K below the set cylinder temperature.
°C
4 8
A
The electronic temperature limiter inside
the burner control unit limits the boiler
water temperature.
Flow temperature setting range: 20 to
74 °C.

Function description

115