NTI Boilers Watertube Boiler 94% AFUE 5:1 Turndown, 800k-Input, 752k-Gross Output, 475 lbs, Water Content-5.2 gallons, 2" FPT Heating Connections, 1" MPT Gas Connection, 6" Vent Size, Dimensions-63-1/2"D x17"W x37"H