Control Specification SiBE12-90843 Function and Control3.4 Controls at Mode Changing / Start-up3.4.1 Preheating OperationOutline Operate the inverter in the open phase operation with the conditions including the preheatingcommand from the indoor, the outdoor air temperature and discharge pipe temperature.Detail Preheating ON Condition When outdoor air temperature is below 10.5ºC and discharge pipe temperature is below10.5ºC, inverter in open phase operation starts. (The power consumption of compressorduring preheating operation is 35 W.)OFF Condition When outdoor air temperature is higher than 12ºC or discharge pipe temperature is higherthan 12ºC, inverter in open phase operation stops.3.4.2 Four Way Valve SwitchingOutline During the heating operation current must be conducted and during cooling and defrostingcurrent must not be conducted. In order to eliminate the switching sound (as the four way valvecoil switches from ON to OFF) when the heating is stopped, the delay switch of the four wayvalve must be carried out after the operation stopped.Detail The OFF delay of four way valveEnergize the coil for 150 seconds after unit operation is stopped.3.4.3 Four Way Valve Operation CompensationOutline At the beginning of the operation as the four way valve is switched, acquire the differentialpressure required for activating the four way valve by having output frequency which is morethan a certain fixed frequency, for a certain fixed time.Detail Staring Conditions1. When starting compressor for heating.2. When the operating mode changes from the previous time.3. When starting compressor for starting defrosting or resetting.4. When starting compressor for the first time after the reset with the power is ON.5. When starting compressor after operation stop by the cooling / heating mode change-overmalfunction.Set the lower limit frequency to Hz for 60 seconds with any conditions with 1 through 5above.3.4.4 3-Minute StandbyProhibit to turn ON the compressor for 3 minutes after turning it off.(Except when defrosting. )40 class 50 classCooling 56Hz 40HzHeating 68Hz 54Hz
