Airwell YBZ214, Service Manual

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CONTROL SYSTEM
12-4 Service Manual – YBZ DCI 1-A.1 GB
12.1.5.2 EEV initial value determination
The EEV initial value (open loop) is determined according to the number of the active indoor
units, mode, and the capacity code of the unit.
12.1.5.3 Balance time
During the balance after SB the correction is not calculated. After that the correction value is
updated every
5
seconds.
12.1.5.4 EEV corrections
The corrections will keep the compressor in the proper operation temperature (Target CTT
control) and will balance between the indoor units by controlling their super heat.
12.1.5.5 EEV opening of inactive indoors
Under Cool Mode/Dry Mode, relative EEV of inactive indoor will be fully closed to 0.
Under Heat Mode, relative EEV of inactive indoor will maintain an opening in a range so that
refrigerant and oil can come back to outdoor.
12.1.6 Reversing Valve (RV) Control
Reversing valve is on in heat mode.
Switching of RV state is done only after compressor is OFF for over 2 minutes.
12.2 Fan Mode
In this mode, the indoor fan may run at high, medium, low and automatic speed. The compressor,
outdoor fan and 4-way valve will be OFF.
In this mode, the range of setting temperature is 16~30C
12.3 Cool Mode
12.3.1 Starting Cool Mode
If the system is in idle, when any one indoor requests the cooling mode operating, the system will
run in Cool Mode. EEV, OFAN and compressor will start operating.
12.3.2 Compressor’s action when Indoor changed to inactive (OFF or
Thermo OFF)
12.3.2.1 All indoors to inactive
Compressor stops immediately, OFAN stops after 1 min.