SiUS041111 Main FunctionsFunction and Control 211. Main Functions1.1 Temperature ControlDefinitions ofTemperaturesThe definitions of temperatures are classified as following. Room temperature: temperature of lower part of the room Set temperature: temperature set by remote controller Room thermistor temperature: temperature detected by room temperature thermistor Target temperature: temperature determined by microcomputerTemperatureControlThe temperature of the room is detected by the room temperature thermistor. However, there isdifference between the “temperature detected by room temperature thermistor” and the“temperature of lower part of the room”, depending on the type of the indoor unit or installationcondition. Practically, the temperature control is done by the “target temperature appropriatelyadjusted for the indoor unit” and the “temperature detected by room temperature thermistor”.1.2 Frequency PrincipleMain ControlParametersThe compressor is frequency-controlled during normal operation. The target frequency is set by thefollowing 2 parameters coming from the operating indoor unit: The load condition of the operating indoor unit The difference between the room thermistor temperature and the target temperatureAdditionalControlParametersThe target frequency is adapted by additional parameters in the following cases: Frequency restrictions Initial settings Forced cooling operationTarget temperatureSet temperatureRoom temperatureRoom thermistor temperature(R12321)
