Daikin UATYA-B, Руководство по эксплуатации

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Service manual Daikin R32 Rooftops UATYA-B
ESIE21-02 – 2021.03
3.13.9 Air change in the room
The external air damper helps the controller manage air change in the room by keeping the dampers open at min. percen -
tage during unit operation.
If a probe is fitted to detect the air quality in the room, the controller can increase the air change rate.
The air quality parameters that the controller can manage include CO
2
“quantity of carbon dioxide” and VOC “volatile orga -
nic compounds”.
This is an essential function in rooms where people's traffic/stay varies significantly during the day.
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
DA12 30 % External air - FC / FH - Min opening
DA13 100 % External air - FC / FH - Max opening
DA19 700 ppm External air - Environment air renewal - CO2 concentration setpoint for activation
DA20 0 ppm External air - Environment air renewal - CO2 concentration offset for regulation
DA21 100 ppm External air - Environment air renewal - CO2 concentration diff. for regulation
DA23 50.0 % External air - Environment air renewal - VOC concentration setpoint for activation
DA24 0.0 % External air - Environment air renewal - VOC concentration offset for regulation
DA25 5.0 % External air - Environment air renewal - VOC concentration diff. for regulation
3.13.10 Co
2
control
Below is a graphical representation with reference to the quantity of CO
2
in the air.
DA20 DA21
DA13
DA12
%
DA19
CO 2 (ppm)
Fig. 29 Damper command for air change with Co
2
probe
In addition to the parameters listed in the table, the abbreviations in the graph are:
- CO
2
= quantity of CO
2
in the air;
- %As = damper opening percentage.
If the CO
2
probe is fitted and the quantity of CO
2
is higher than the setpoint in parameter “DA19” plus the offset value stored
in parameter “DA20”, the controller increases the percentage of external air within the differential set in parameter “DA21”.
The setpoint ranges between the min. value stored in parameter “DA12” and the max. value in parameter “DA13”.
Damper opening may be limited with respect to the max. value set in parameter “DA13” as a result of problems with tempe
-
rature or pressure, as described in the chapter on limitations.
3 Software functions