5
Functions of the heating circuit
Which controller functions are available depends on the selected system code number (Anl).
5.1 Functioning principle
The heating circuit with the highest flow set point has priority. This principle applies to all heat-
ing circuits with mixing valves. In systems Anl 3, 5 and 8, the pump circuit has priority. The flow
set point of the heating circuit with priority is controlled by the valve in the pre-control circuit.
If several heating circuits have the same flow set point, the heating circuit with lowest number al-
ways has priority and is controlled by the primary valve.
5.2 Weather-compensated control
When weather-compensated control is used, the flow temperature is controlled according to the
outdoor temperature. The heating characteristic in the controller defines the flow temperature
set point as a function of the outdoor temperature (–> Fig. 2).
Function
WE
Configuration
Outdoor sensor AF1, 2, 3
Co1, 2, 3 -> Fb02 = ON*
* Co1 -> Fb02 cannot be deactivated
EB 5179 EN
39
Functions of the heating circuit
130
120
110
100
90
80
70
60
50
40
30
20
20
16
12
8
4
0
-4
-8
-12
-16
-20
2.4
3.2
2.9
2.6
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.4
0.2
[
˚
C]
[
˚
C]
t
VL
t
A
Fig. 2 · Gradient characteristics
t
VL
Flow temperature
t
A
Outdoor temperature
