7002 Interval for long term average outside temperature
Averaging interval for calculating the adjusted outside
temperature (long term average).
This outside temperature is for example used for:
■
Calculating the set flow temperature from heating or
cooling curve
Changeover between central heating and central
■
cooling mode
The continuous averaging of actual temperatures
reduces the influence of brief temperature fluctuations.
The mathematical method applied acts like an attenua-
tion. With this attenuation, the adjusted outside tem-
perature achieves the following values after a sudden
temperature change:
■
63 % of the change after a single averaging interval
■
95 % of the change after three averaging intervals
ϑ
100%
63%
37%
AB
AB
Fig. 50
A
Time of the sudden temperature change
Expiry of one averaging interval
B
7003 Temperature differential for calculating the heating limit
Heating limit:
Set room temperature minus "Temperature differen-
tial for calculating the heating limit 7003".
Central heating starts automatically if the adjusted out-
side temperature (long term average, averaging inter-
val in the delivered condition 3 h) falls below the heat-
ing limit. The operating program "Heating and DHW"
must be active.
In practical use, this characteristic results not only in
an adjustment but also a delay in capturing the outside
temperature.
ϑ
Fig. 51
Outside temperature (not adjusted)
A
Adjusted outside temperature
B
Note
For other functions, the control unit calculates a short-
term average outside temperature (averaging interval
2 min).
Setting in min
t
Example:
Selected set room temperature = 20 °C
"Temperature differential for calculating the heat-
ing limit 7003" = 4 K
This results in a heating limit of 16 °C (20 °C
■
Adjusted outside temperature < 16 °C (heating limit):
Central heating starts.
Adjusted outside temperature
■
fied hysteresis of 2 K):
Central heating is stopped.
Parameter group System definition
!
A
B
t
!
18 °C (due to speci-
>
4 K).
–
197