Daikin R-32 rooftop Series, Operation Manual

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Translation from original instructions
Packaged Rooftop
20
We reserve the right to make changes without any prior notice.
UATYA
4P645203-1
5.2.3 Dynamic setpoint from external air probe in heating mode
The setpoint value entered in parameter “STH1” 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
STH1 40 °C Mechanical heating / Auxiliary heating in winter mode - Temperature setpoint
SD20 15.0 °C
Mechanical heating - External air temperature - Activation threshold for
compensation
SD21 10.0 °C Mechanical heating - External air temperature - Activation differential
SD22 5.0 °C
Mechanical heating - External air temperature - Max increase / decrease of the
setpoint
A graphical representation is shown below.
Text °C
SD22 > 0
STH1
STH1 - SD22
SD21
SD20
SD22 < 0
STH1 + SD22
Fig. 2 Change in setpoint as the air temperature changes in heating mode
Where “Text” 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 heating
mode is as follows:
- if the external air temperature is higher than the setpoint in parameter “SD20”, the value of the control setpoint is
the value stored in parameter “STH1”;
- if the external air temperature is lower than the setpoint in parameter “SD20”, minus the value in parameter
“SD21”, the value of the control setpoint is given by the sum of the values stored in parameters “STH1” and
“SD22”;
- if the external air temperature is between the values of parameter “SD20” and the difference of the values stored
in parameters “SD20” and “SD21”, the value of the control setpoint varies proportionally between the value stored
in parameter “STH1” and the sum of the values stored in parameters “STH1” and “SD22”.
Parameter “SD22” can have positive or negative values. When the value is negative, parameter
“SD22” has to be subtracted from the value of parameter “STH1”.