SiMT041311E Control SpecificationFunction and Control 522.8 Dew Prevention ControlOutline Cooling the air around us means that the air is dehumidified (condensation of water on theindoor heat exchanger). But because the air is cooled down, less moisture can present in the airand as a consequence the relative humidity of the air rises. When the relative humidity of theoutlet air nears 100%, water may be blown out. To prevent this from happening, the unitchanges, its target evaporating temperature and the frequency of the compressor under certaincircumstances. Normally speaking, even under these conditions (dew prevention safety active),the room should still be cooled down, only slower. Of course, if the capacity of the indoor unit issmall in comparison to the heat load, this is not the case and capacity shortage complaints mayfollow.Detail When the indoor heat exchanger temperature is lower than the target temperature of theindoor heat exchanger, the compressor frequency decreases by 2 Hz in every minute. The target temperature of the indoor heat exchanger is calculated with the room temperatureand the indoor humidity.2.9 Outdoor Fan Control1. Fan OFF delay when stoppedThe outdoor fan is turned OFF 70 seconds after the compressor stops.2. Fan ON control to cool down the electrical boxThe outdoor fan is turned ON when the electrical box temperature is high while the compressoris OFF.3. Fan OFF control during defrostingThe outdoor fan is turned OFF during defrosting.4. Fan ON/OFF control when operation starts / stopsThe outdoor fan is turned ON when the operation starts. The outdoor fan is turned OFF whenthe operation stops.5. Fan speed control during cooling operationThe rotation speed of the outdoor fan is fixed. However, when the outdoor temperature is low,the unit may lower the fan rotation frequency to set a pressure difference. Also, when theoutdoor temperature is high, the unit may raise the fan rotation frequency to cool the electricalbox.6. Fan speed control during heating operationThe rotation speed of the outdoor fan is fixed. However, when the outdoor temperature is high,the unit may lower the fan rotation frequency to set a pressure difference.Class Cooling25 class 710 rpm35 class 780 rpm50 class 860 rpmClass Heating25 class 700 rpm35 class 780 rpm50 class 820 rpm
