Abstract: A water heater includes a tank 10 arranged inside a casing 20 with a burner 16 below the tank so that a heat exchange zone 15 surrounding the tank receives the combustion products. The tank 10 is supported on three edge contact projections 26 resting on ledges 27 located a substantial distance up the sides of the tank. The casing 20 narrows in the upwards direction and a heat shield 30 is coaxially located in the lower portion of the casing where the hottest gases are. A downwardly extending flue 49 outside the casing provides a heat trap. The burner 15 has a burner ring 60 with a unique arrangement of burner ports 62 and a secondary air guide 80. The thermostat probe 14 for the gas valve 17 passes through the heat exchange zone 15 to be intentionally affected by the heat and reduce the achieved operating temperature differential.

Abstract: A water heater including a water tank, a combustion chamber beneath the tank, a gas burner in the combustion chamber, an air plenum upstream of the combustion chamber, a flame arrestor located such that air in the air plenum passes through the flame arrestor to reach the combustion chamber, and a flue extending upwardly from the combustion chamber and through the water tank.

Abstract: A water heater enclosure and kit having a box-like configuration, with a top panel, a pair of opposing side panels secured to the top panel at upper ends, front and rear braces which secure the lower ends of the side panels together, and a removable access panel. The top panel has a pair of side rails having inverted U-shaped mounting channels which receive and seat upper edges of the pair of side panels. Once seated, bendable upper-joint tabs on the side panels are bent around end flanges of the mounting channels to secure the side panels with the top panel. The front and rear braces have lower-joint tabs which extend into slots on lower corners of the side panels and are also bent to form and maintain the lower joints.