Viessmann Cascade control unit Installation, Operating And Service Instructions page 24

Functions
Set flow temperature
Set values (multi-boiler control unit)
Outside temp.
low end
Flow temp.
low end
Design temp.
outside
Design temp.
flow
Heating curve
slope
Flow temp.
minimum
Flow temp.
maximum
24
(cont.)
In most cases, this value represents the set room
temperature in standard mode.
20ºC
Generally with radiator systems, this value
corresponds to the low end temperature.
20ºC
A higher setting is recommended for convector
heating systems.
Design temperature according to the climatic
zone.
10ºC
Max. required flow temperature in accordance
with the size of the heating surfaces.
80ºC
Adjust the slope factor of the heating curve in
line with the heating surfaces used.
1.33
In the "as-delivered condition", this value is set
to 1.33 (radiator heating system).
Standard values for the slope factor:
H Radiator heating system:
H Convector heating system:
H Underfloor heating system: 1.10
Minimum flow temperature.
1ºC
Maximum flow temperature.
74ºC
1.25 to 1.35
1.40