The PH4-12R-01 12000 BTU Dual Hose Portable Air Conditioner and Heater employs Self-evaporative cooling: as part of the cooling process - all air conditioners remove water from the air. These units remove much of this collected moisture by evaporating the moisture into the exhausted air from the unit's exhaust hose. Ultimately this means no water or less water to manually empty depending on your conditions.