A ventless air conditioner works by blowing air through a material that is partially soaked in water, creating cool air through the evaporation of water. The technical term for a ventless air conditioner is an evaporative air cooler, but it is more commonly known as a swamp cooler.
Evaporative air coolers have low power usage because it only requires energy to run the internal fan and timer mechanism. The machines also do not have a refrigeration process, which is why they do not require hot exhaust vents. The lack of vents makes air coolers more portable than air conditioners. The water in the tank has to be refilled.
The disadvantage of evaporative air coolers is that they lose effectiveness in areas with high humidity. The climate has to be dry for the machine to blow cool and moist air into a room. The machines work well in climates with less than 50 percent humidity. In more humid climates, an air conditioner with a vent tends to be a better option.
Companies that sell evaporative air coolers include Sunpentown, KuulAire, Luma Comfort and Living Basix. Features available on certain models include digital control pads, ionizers to keep the air clean and large capacity water tanks capable of holding several gallons of water.