Daikin UATYA-B, Operation Manual

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Service manual Daikin R32 Rooftops UATYA-B
ESIE21-02 – 2021.03
The value set in parameter “HU11” identifies the reference humidity value, as follows:
- 0 = relative humidity;
- 1 = absolute humidity.
Normally, absolute humidity control helps obtain a higher level of precision in maintaining the desired humi -
dity setpoint, if compared to relative humidity control.
The value set in parameter “HU12” identifies the type of humidity control, as follows:
- 0 = proportional.
- 1 = PID.
The value set in parameter HU14” identifies the control probe type, as follows:
- 0 = relative humidity probe on air return line;
3.4.1 Relative humidity control with proportional control
If parameter “HU11” is set to “0”, humidity control is performed according to the relative humidity value.
Relative humidity is managed according to parameter “HU14”, which identifies the probe on which the controller must gua
-
rantee maintenance of the entered setpoint, and on parameter “HU12” that determines the type of humidity control.
The parameters involved are shown in the table.
The values of the parameters are representative. In specific cases, different values can be set.
Parameter Value UM Description
HU1 58.0 % Relative humidity setpoint
HU2 35.0 % Min. relative humidity setpoint
HU3 65.0 % Max. relative humidity setpoint
HU4 5.0 % Relative humidity control differential
HU5 0.5 % Relative humidity control neutral area
A graphical representation is shown below.
HU4
100
0
%
HU4
HU5
HU1
SdR %
HU5
Fig. 10 Relative humidity control
3 Software functions