Lochinvar® FTXL™ Fire Tube Boiler Boiler With Control and Safety Device, Model: FTX725, 120 V, 6 A, 21.7 hp Power, 60 Hz Frequency, 1 ph, Up to 98.3 % AFUE, 725000 Btu/hr BTU, 17 gal Capacity, 71 gpm Flow Rate, 160 psi Pressure, NPT Connection, Natural Gas Fuel, Direct Vent, Modulating Burner, CFM Rating: 150 cfm, Chimney/Breeching/Vent Size: 6 in, 705000 Btu/hr DOE Heating, Ignition System: Direct Spark, Direct Spark Ignition, Net BTU Rating: 613 mbh, 84.6 sq-ft Area, Wall Mounting, Stainless Steel, Dimensions: 53-1/4 in H x 26-1/4 in W x 23-1/2 in D, Additional Information: 1 in Gas Connection, 2-1/2 in Water Connection