There is an overseas function in older units that was designed to capture the cold air from the iStore and duct that to the kitchen, it was termed fan mode. There was a trap where if the electric booster button is held for an extended period the fan mode is started in either slow or fast speed. To clear the fan mode simply press and hold the booster button until the fan icon moves from 1/2 fan to full fan and then the icon turns off, let go and the fan should stop. NOTE if the unit is heating at that time the fan will stay on until the end of the heat cycle.