SiBE04-624 Control SpecificationFunction and Control 733.13 Automatic DefrostingDefrost Control Start Conditionis calculated by the following formula:= –17/256 × compressor operation frequency + 43/64 × outside air temperature – 6However, when the calculated value is less than the lower limit indicated in the table below, thelower limit is adopted as .Operation during Defrosting and Termination Condition• Operation should be conducted at 64Hz during defrosting.• Defrosting operation must be conducted for 2 minutes, and after that, defrosting operation isconducted until the outdoor heat exchanger temperature reaches the defrost cancellationtemperature at ºC.• After the temperature has reached the defrost cancellation temperature, the defrostingshould be terminated.is calculated by the following formula:= 18 – 22/64 × outside air temperatureHowever, when the calculated value is outside the range between 6ºC and 22ºC, if it is less than6ºC, 6 should be adopted and if it is more than 22ºC, 22 is adopted, as the defrost cancellationtemperature.Outside air temperature condition Lower limit–4ºC ≤ outdoor air temp –15ºC–10ºC ≤ outdoor air temp. < –4ºC –20ºCoutdoor air temp. < –10ºC –22ºCDefrost control startsandorHeating modeandHeating modeCompressor is in operation6 or more minutes passed since thecompressor started its operationThe cumulative time of heating operationreached 25 minutes or moreThe cumulative time of heating operationreached 4 hours or moreOutdoor heat exchanger temperature< 0ºCThe state that the outdoor heat exchangertemperature < ºC has continued for 1minute or more
