When the outdoor temperature is low and the unit is high, using the heating mode will result in ice being created inside the outdoor unit, decreasing its heating capacity. A built-in microprocessor is used to monitor this condition and when necessary, the defrost mode goes into operation, resulting in a temporary interruption of the heating mode and both the internal and external fans will interrupt its operation. About 7 to 15 minutes will be required for the operation to resume. During defrost mode, the operation indicator light will come on. When the process is finished, normal heating operation will return.
