Viessmann Vitotronic 200 Installation And Service Instructions Manual page 73

Heating circuit control
Party and economy keys on all control
units have no function.
Frost protection
In the case of outside temperatures
below +1 ºC a minimum flow tempera-
ture of 10 ºC is ensured. For changes
see coding address "A3", variable
frost limit.
Therm-Control
The output is reduced if the actual
temperature at the Therm-Control
sensor falls below the set tempera-
ture. This connects the mixer of down-
stream heating circuits.
Raising the reduced room temperature
During operation with reduced room
temperature, the reduced set room
temperature can be automatically
raised subject to the outside tempera-
ture. The temperature is raised in
accordance with the selected heating
curve, but no higher than the set stan-
dard room temperature.
(cont.)
The outside temperature limits for the
start and end of the temperature rais-
ing can be adjusted via coding
addresses "F8" and "F9".
Function description
73