DESC: The Amcor PLM16000EH portable air conditioner with heater is designed to condition an average-sized rooms up to 500 sq. ft. Patented Evaporative Booster Technology - During the cooling process, water is extracted from the air as it passes through the unit. Most of this water is used to cool the unit and make it run more efficiently. This unit has a built-in water tank (not removable) with a drain outlet. When the tank fills, the compressor stops running. This indicates that the tank should be emptied.