Airwell KXV Series, Engineering Manual

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Engineering manual
52
5 EEV(Electronic Expansion valve) control
5.1 EEV general rules
5.1.1 Operation Range
The EEV operation range is defined according to the operation mode as follows:
Indoor EEV Outdoor EEV
ODU Mode
Active IDU Inactive IDU Main
Stand By 0steps 480steps
COOL 60steps to 460steps 0steps 480steps
HEAT 60steps to 450steps 45steps 100steps to 450steps
5.1.2 EEV resetting (homing)
When ODU is Power On, ODU Main will be reset. The process about reset is shown in the below graph: first EEV is
opened 240 steps, is closed 520 steps, and then is opened 480 steps, 40 seconds later EEV is closed 0 steps.
5.1.3 Start and Opening Determination

EEV start rule:
Every time EEV start, the EEV goes to Open loop setting then goes to EEV correction Control.

EEV correction Control:
EEVi(n) = EEVi(n-1) + EEVCVi

The target EEV will be limited to the minimum and maximum operation range.
Table 5-1
Chart 5-1