The Fan/Aux box has 3 outputs so that a heater, humidifier, dehumidifier and fan can be connected to the Dimlux Maxi Controller. All outputs are 15A. The fan control is electronic and quiet in use (no humming). The fan controller has a temperature control and an RH day and night to control which are individually adjustable. The temperature controller works by means of SmartLogic, this is an algorithm that ensures that the current temperature is actually equal to the set temperature.