3.5 Ton Ultra Low NOx Single Stage Convertible Natural Gas/Electric Packaged Unit, Volts: 230, Hertz: 60, Phase: 1, Refrigerant: R410A, Department of Energy Guide SEER2 (Range): 13.4, CFM: 1663, BTU Input: 100,000, BTU Output: 81,000, Cooling BTU: 42,000, Heating BTU: 100,000, Factory Charge: 61 oz, Overall Dims: 43''H X 47-1/2''W X 55-4/5''D, Weight: 438 lbs **Ultra Low NOx Unit is not LP Compatible**