Lochinvar® KNIGHT® Fire Tube Boiler Boiler With ECM Pump, Model: WHB055, 120 V, 1.8 A, 60 Hz Frequency, 1 ph, 95 % AFUE, 55000 Btu/hr BTU, 2.3 gal Capacity, 5 gpm Flow Rate, 80 psi Pressure, MNPT Connection, Natural Gas Fuel, Direct Vent, Modulating Burner, Chimney/Breeching/Vent Size: 2 in, 51000 Btu/hr DOE Heating, Ignition System: Direct Spark, Direct Spark Ignition, Net BTU Rating: 44 mbh, Number of Boilers: 8, 5.92 sq-ft Area, Wall Mounting, Stainless Steel, Dimensions: 40 in H x 18-3/4 in W x 16 in D, Additional Information: 1/2 in Gas Connection, 1 in Water Connection