Viessmann FB2A Installation And Service Instructions For Contractors page 117

Control functions
Example using the settings in the delivered condition
90
80
70
60
50
40
30
A Heating curve for operation with
standard room temperature
Reducing the heat-up time
During the transition from operation with
reduced room temperature to operation
with standard room temperature, the
boiler water or flow temperature will be
raised in accordance with the selected
heating curve. The boiler water or flow
temperature can be automatically
increased.
(cont.)
10 5 0 -5 -10 -15
Outside temp. in °C
B Heating curve for operation with
The value and duration of the additional
increase of the set boiler water or flow
temperature can be adjusted in coding
addresses "FA" and "Fb".
Function description
A
B
-20
reduced room temperature
117