Richmond Essential Water Heater, Inlet Connection Size: 1/2 in, BTU Rating: 36000 Btu, Gas Type: Natural Gas, 64 gph, Tank Capacity: 40 gal, Energy Efficiency: 0.65, Vent Type: Power, Vent Size: 62-1/2 in, Water Connection Location: Top, Tank Height: 51 in, Dimensions: 21-3/4 in Dia x 51-1/4 in H, Includes: Factory Installed T and P Relief Valve