NTI Boilers Firetube Boiler 96% AFUE 8.5:1 Turndown, 2000k-Input, 1,920k-Gross Output, 1710 lbs, Water Content-51 gallons, 3" Groove Joint Heating Connections, 1-1/2" MPT Gas Connection, 8" Vent Size, Dimensions-60-5/16"D x33-7/8"W x66-1/4"H