The Single Most Effective Way of Self Cleaning Your Aircon Revealed!!! Its your Remote Controller! After a night of usage, DO NOT off your aircon immediately when you wake up, instead do the following: - Set your mode from "Cool" to "Fan" mode, set Fan Speed to high. - Let it run for 15 minutes. Setting to fan mode will not activate the compressor, thus only the fancoil fan blower is running with normal (not cold) air blowing out, this will dry up the internal of the aircon unit of moisture, minimizing the build up of Mould and Mildew.