
An air conditioner has several ways of sounding a warning siren that it needs professional repairs. One of those sirens is, appropriately, odd noises.
Modern air conditioners run quieter than ever, but you’ll still hear a similar set of sounds while one operates: the whir of the blower fan, the movement of air through the vents, the hum of the compressor, the occasional drip of water, and brief clicking as the unit powers down. When different sounds intrude or the AC starts becoming much louder than before, pay close attention—these sounds give you an idea of what’s wrong and when it’s time to call for a professional to fix it.