SiUS041111 Control SpecificationFunction and Control 433.10 Defrost ControlOutline Defrosting is carried out by the cooling cycle (reverse cycle). The defrosting time or outdoor heatexchanger temperature must be more than a certain value to finish.Detail Conditions for Starting Defrost The starting conditions are determined with the outdoor temperature and the outdoor heatexchanger temperature. The system is in heating operation. The compressor operates for 6 minutes. More than 28 minutes of accumulated time pass since the start of the operation, or ending theprevious defrosting. (09/12 class) More than 15 ~ 25 minutes (depending on the duration of the previous defrost control) ofaccumulated time have passed since the start of the operation, or ending the previousdefrosting. (15/18/24 class)Conditions for Canceling Defrost 09/12 classThe judgment is made with outdoor heat exchanger temperature. (4 ~ 22°C, 39.2 ~ 71.6°F)FrequencyCompressorFour way valveFanONOFFONOFFONOFF0 Hz72 Hz84 Hz 90 Hz5 sec.380 pulse360 pulse450 pulse450 pulseInitial openingPI control5 sec.40 sec.40 sec. 630 sec.60 sec.(R14666)Electronic expansionvalve opening
