SiENBE04-507AFunction and Control 45Part 4Function and Control1. Main Functions......................................................................................461.1 Frequency Principle................................................................................461.2 Air Flow Direction Control.......................................................................481.3 Fan Speed Control for Indoor Units........................................................491.4 Programme Dry Function .......................................................................501.5 Automatic Operation...............................................................................511.6 Thermostat Control.................................................................................521.7 NIGHT SET Mode ..................................................................................531.8 ECONO Mode ........................................................................................541.9 INTELLIGENT EYE ................................................................................551.10 Inverter POWERFUL Operation .............................................................571.11 Other Functions......................................................................................582. Function of Thermistor ..........................................................................592.1 Heat Pump Model...................................................................................592.2 Cooling Only Model ................................................................................603. Control Specification .............................................................................613.1 Mode Hierarchy ......................................................................................613.2 Frequency Control..................................................................................623.3 Controls at Mode Changing / Start-up....................................................643.4 Discharge Pipe Control ..........................................................................653.5 Input Current Control..............................................................................663.6 Freeze-up Protection Control .................................................................673.7 Heating Peak-cut Control .......................................................................673.8 Fan Control.............................................................................................683.9 Liquid Compression Protection Function 2.............................................683.10 Defrost Control .......................................................................................693.11 Electronic Expansion Valve Control .......................................................703.12 Malfunctions ...........................................................................................733.13 Forced Operation Mode .........................................................................743.14 Additional Function.................................................................................743.15 Facility Setting Jumper (cooling at low outdoor temperature) ................75