Abstract: The water heater includes a burner and a water tank. Combustion products flow upwardly around the tank through a combustion products path where heat transfer to water in the tank occurs, the path being defined between the outer wall of the tank and a surrounding heat exchanger wall. The combustion products pass through outlet at the upper end of wall, and enter the flue which includes a down flow passage and then pass out through discharge outlet. The down flow passage is defined between a flue outer wall and a thermally conductive partition defining the inner wall of the passage. The partition is adjacent a heated zone of the water heater where stored heat of the water heater is available during quiescent or standby periods when the burner is not operating. The partition between the heated zone and the down flow passage provides a heat transfer path so that heat in the heated zone can transfer through the partition to gases in the down flow passage.

Abstract: The water heater includes a water tank, a burner below the tank, a casing around the outside surface of the tank and spaced therefrom so as to define a flue path within the casing and along the outside surface of the tank for combustion products. Multiple flow restrictions are located in the flue path and extending inwardly from the casing towards the outside surface of the tank and forming regions of restricted flow area so that the combustion products flowing along the flue path encounter the flow restrictions and are restricted and disturbed in flow pattern. The first flow restriction which is first encountered by the combustion products is located at a position along the height of the tank no lower than one third of the overall height of the tank up from the bottom of the tank whereby the lower portion of the tank over which combustion products are flowing are substantially completely exposed to the hottest and most turbulent combustion gases.

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 hot water heater capable of delivering a relatively large quantity of hot water, the quantity being larger than the total volume of the storage capacity of the heater is disclosed.The hot water heater comprises a vessel having an inlet port and an outlet port, a cold water inlet coupled to the inlet port, a hot water outlet line coupled to the outlet port, with heating means for heating water in the vessel, and control means for establishing a flow path between the inlet and outlet lines. The arrangement is such that water flowing in the inlet line is divided between the flow path and inlet port in a predetermined ratio whereby water flowing in the outlet line is, in use, colder than the water passing through the outlet port.

Abstract: A hot water heater comprises a vessel, a heating means for heating water in the vessel, and a control conduit for diverting cold water from the cold water inlet to the hot water outlet so as to reduce the temperature of the hot water delivered from the vessel but to increase the volume. The heater includes a control means for selectively energizing the number of heating elements in accordance with the temperature of the water in the vessel. When the heating means comprises a gas burner, it is arranged to direct combustion gases towards one side of the vessel so as to establish a convection current within the vessel. A novel flue arrangement is also disclosed.