Patent ID: 8621884

Claim:
An air conditioning unit including an evaporator, a condenser, a compressor, and a supply fan that selectively cools an enclosure with ambient air from an ambient environment, the air conditioning unit comprising: an intake vent capable of receiving cool ambient air; an exhaust vent capable of discharging warm air to the ambient environment; a return vent that receives warm air from the enclosure; a supply vent that provides cool air to the enclosure; and an economizer assembly including a sliding damper and a partition, the partition including an opening through which air can flow from the return vent to the supply vent across the evaporator during a mechanical cooling mode; the sliding damper including a vertical panel and an angled panel, the vertical panel capable of moving vertically to close the intake vent and the exhaust vent during the mechanical cooling mode, the angled panel capable of closing the opening in the partition in order to enter an economizer mode in which the supply fan pulls cool ambient air from the intake vent to flow to the supply vent and warm air flows from the return vent to the exhaust vent.