4. Description of the controller functions
The following function descriptions are intended to help you understand the settings required for
operation.
The controller functions depend on the selected system code numbers (1 to 6). See chapter 5 for
details.
4.1 Optimize
The controller is capable of automatically determining the most favorable times for activa-
tion/deactivation of the heating system in periodically occupied buildings. To activate this func-
tion, select function block setting FB 0 = ON (linked to FB 13 = ON).
In contrast to the reduced operation, the heating system is deactivated at the latest when the
time of non-use starts. A reference room with an installed room temperature sensor is moni-
tored in place of the entire building. Whenever the room temperature falls below an adjustable
Sustained temperature, the controller activates the heating until the temperature exceeds the
sustained temperature (plus approx. 0.5°C differential gap) again. To achieve this, the system
can be run at the maximum permissible flow temperature.
The controller determines when the heating should be activated to start rated operation of the
system so that the Room temperature set point (temperature adjustable at the controller) is just
reached when the set time-of-use begins. The heating may be activated up to 6 hours before the
set time-of-use begins (this is the case on start-up as the controller has not yet stored any infor-
mation concerning the building characteristics).
Drinking water is not heated in system code numbers 2 and 3 during the preheating time. The
controller determines when the heating is to be deactivated so that the temperature does not fall
significantly below the desired room temperature towards the end of time-of-use due to the
heating being deactivated before the time-of-use ends (e.g. direct sunlight can cause an in-
crease in room temperature, especially if the flash adaptation is not used, and this in turn leads
to the system being deactivated too soon). The heating may be deactivated up to 2 hours before
the set time-of-use ends.
If 2 rated operation times are set for one day, the controller does not monitor the Sustained tem-
perature, but a Reduced room temperature set point (the temperature adjustable at the con-
troller) between both time blocks.
4.2 Adaptation
The controller is capable of automatically adapting the heating characteristic to the building
characteristics. Based on the default heating characteristic (gradient value 1.8), a reference
room with an installed room temperature sensor is monitored in place of the entire building. If
the measured room temperature deviates from the adjustable Room temperature set point on
the average during the time-of-use when the mode switch is set to , the subsequent rated
operation time is based on the altered heating characteristic gradient, provided the function
block setting is set to FB 1 = ON. The corrected value is displayed in the parameter level as
Gradient of the heating; this parameter cannot be accessed to change it manually when the
adaptation mode (FB = 1) is selected.
Immediate responses to deviations in room temperature can be achieved using the function
block setting FB 2 = ON: the flash adaptation compensates for deviations in room temperature
during time-of-use when the mode switch is set to , by lowering or raising the heating char-
acteristic by up to 30 °C (parallel displacement of the heating characteristic). Combined with
adaptation mode (FB 1 = ON), a maximum displacement of 5 °C is designated.
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