Input BTU/hr(max) 390,000 990,000 1,500,000 2,000,000 DF-BG Series (1.8-9) Model DF 1.8 BG DF 4 BG DF 6 BG DF 9 BG Width 24" 46" 46" 64" Length 84" 108" 132" 164" Height 30" 44" 48" 68.... 30 amp. 30 amp. 30 amp. Duct Size 10" 16" 18" 24" DF-BG Series (11-21) Model DF 11 BG DF 17 BG DF 21 BG Width 72" 84" 90" Length 168" 176" 186" Height 72" 89" 96" Weight (lbs... area AH Series Model AH-4 AH-9 AH-15 AH-20 Length (inch) 60 84 86 130 Width 24 34 40 56 Height 26 36 42 51 Weight (lbs) 450 880 1,200 1,200 ACFM (Blower) 1,800 5,000 9,000 12,000...