Abstract: A hot water heater of a low profile, box-shaped design, with the height and width remaining generally constant, and the length being dependent on the volumetric capacity desired for the water heater. The water heater is configured for horizontal configuration or vertical mounting and includes a cold water inlet for allowing input of cold water into a lower compartment. A baffle plate divides the lower compartment from an upper compartment, and water from the cold water inlet flows through a baffle opening, or delivery outlet, into the upper compartment. While in the lower compartment, the water is subjected to heating by at least one heating element, which serves to pre-heat the water. As the water flows to the upper compartment, it is heated further by at least one additional heating element located in the upper compartment.