SiEBE18-526 Special ControlFunction 653.4 Pump-down Residual OperationWhen activating compressor, if the liquid refrigerant remains in the heat-exchanger, the liquidenters into the compressor and dilutes oil therein resulting in decrease of lubricity.Therefore, the pump-down residual operation is performed to collect the refrigerant in the heat-exchanger when the compressor is down.3.4.1 Pump-down Residual Operation in Cooling Operation3.4.2 Pump-down Residual Operation in Heating Operation3.5 Restart StandbyRestart is stood by force to prevent frequent power-on/off and to equalize pressure in therefrigerant system.Actuator Outdoor unit operationCompressor 124 HzOutdoor unit fan Fan controlFour way valve OFFMain electronic expansion valve (EV1) 2000 plsSubcooling electronic expansion valve(EV2) 0 plsHot gas bypass valve (SVP) OFFReceiver gas discharging valve (SVG) ON → OFFEnding conditions • 30 sec.• Pe<0.5 MPa• Td>110°CorActuator Outdoor unit operationCompressor 52 → 124 HzOutdoor unit fan STEP8Four way valve ONMain electronic expansion valve (EV1) 0 plsSubcooling electronic expansion valve(EV2) 0 plsHot gas bypass valve (SVP) ON → OFFReceiver gas discharging valve (SVG) ON → OFFEnding conditions • 3 min.• Pe<0.25 MPa• Td>110°CorActuator Operation RemarksCompressor OFF ⎯Outdoor unit fan OFF ⎯Four way valve Keep former condition. ⎯Main electronic expansion valve (EV1) 0 pls ⎯Subcooling electronic expansion valve(EV2) 0 pls ⎯Hot gas bypass valve (SVP) OFF → ON ⎯Receiver gas discharging valve (SVG) OFF ⎯Ending conditions 5 min. ⎯
