Residential Gas Water Heaters Vertex™ Continuous hot water, shower after shower! The more hot water you need, the more you need a Vertex water heater. Through an inspired blend of innovation, efficiency and years of industry expertise, A. O. Smith has created a family of state-of-the-art products that provide a long-lasting supply of hot water during those times when everyone in your home needs it most. Vertex™ power-vent and power direct-vent gas water heaters take high-demand homes to the pinnacle of hot water availability. Vertex offers up to 96% thermal efficiency with performance that rivals much larger water heaters. With its fully-condensing design, Vertex delivers “continuous hot water” — shower after shower, hour after hour. Yet it’s easy to install, with dimensions and installation requirements comparable to standard power-vent and power direct-vent units.