Daikin UATYA-B, Operation Manual

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Service manual Daikin R32 Rooftops UATYA-B
ESIE21-02 – 2021.03
3.2.2 Dynamic setpoint from external air probe in cooling mode
The setpoint value entered in parameter “ST1” is “compensated” against the external air temperature.
The parameters concerned are shown in the table.
The values of the parameters are representative. In specific cases, different values can be set.
Parameter Value UM Description
ST1 27.0 °C Mechanical cooling - Temperature setpoint
SD2 1 - States of the unit in which it is active
SD10 25.0 °C Mechanical cooling - External air temperature - Activation threshold for compensation
SD11 15.0 °C Mechanical cooling - External air temperature - Activation differential
SD12 -5.0 °C
Mechanical cooling - External air temperature - Max increase / decrease of the
setpoint
A graphical representation is shown below.
T
ext
°C
SD12 > 0
ST1
ST1 - SD12
SD11
SD10
SD12 < 0
ST1 + SD12
Fig. 1 Change in setpoint as the air temperature changes in cooling mode
Where “T
ext
” is the value of the external air temperature.
When this function is enabled, the setpoint value that the controller uses to manage the air temperature in cooling mode is
as follows:
- if the external air temperature is lower than the setpoint in parameter “SD10”, the value of the control setpoint is the
value stored in parameter “ST1”;
- if the external air temperature is higher than the setpoint in parameter “SD10”, plus the value in parameter “SD11”, the
value of the control setpoint is given by the sum of the values stored in parameters “ST1” and “SD12”;
- if the external air temperature is between the values of parameter “SD10” and the sum of the values stored in parame -
ters “SD10” and “SD11”, the value of the control setpoint varies proportionally between the value stored in parameter
“ST1” and the sum of the values stored in parameters “ST1” and “SD12”.
Parameter “SD12” can have positive or negative values. When the value is negative, parameter “SD12” has
to be subtracted from the value of parameter “ST1”.
3 Software functions