Rheem® Endeavor Premium-Grade Variable Speed Gas Furnace, Classic Series, R921V Model, 42000 Btu/hr Input BTU Rating, 39900 Btu/hr Output BTU Rating, 115 V Voltage Rating, 10 A Amperage Rating, 300 to 1240 cfm Rating, 1/2 hp HP Rating, 92 % AFUE Rating, 373 W Wattage, 1 ph Phase, 60 Hz Frequency Rating, 1 Number of Stages, 4-Way, Multi-Position Configuration, Connection Type: NPT, 1/2 in Connection, Electric Fuel Type, 11 in Dia x 7 in W Blower Size, 34 in H x 17.5 in W x 29.63 in D Cabinet Dimensions, ECM Motor Type, 3 ton Tonnage, Electronic Ignition System, Direct Spark Ignition Type, 0.25 kPa, Stainless Steel/Steel, 20 to 50 deg F Temperature Rise, Domestic Domestic/Import