Abstract: The storage tank portion of a water heater has an outwardly projecting threaded pipe coupling fitting and is disposed within a jacket structure that forms an enclosed insulation space around the storage tank, the outer end of the pipe coupling fitting being spaced inwardly apart from a pipe connection opening in the jacket structure. A generally tubular foam stop member having a convexly curved side portion is positioned within the insulation space before the space is filled by an injection process with a liquid foam insulation material. The foam stop member receives the pipe coupling, is axially pressed between the storage tank and the jacket structure, and forms a seal around the pipe coupling fitting and around the jacket structure pipe connection opening.

Abstract: The storage tank portion of a water heater has an outwardly projecting threaded pipe coupling fitting and is disposed within a jacket structure that forms an enclosed insulation space around the storage tank, the outer end of the pipe coupling fitting being spaced inwardly apart from a pipe connection opening in the jacket structure. A generally tubular foam stop member having a convexly curved side portion is positioned within the insulation space before the space is filled by an injection process with a liquid foam insulation material. The foam stop member receives the pipe coupling, is axially pressed between the storage tank and the jacket structure, and forms a seal around the pipe coupling fitting and around the jacket structure pipe connection opening.

Abstract: An inlet water turbulator body is coaxially secured within the lower end of an inlet water supply dip tube vertically disposed with the storage tank portion of a water heater. A spaced plurality of vertically spiraling passages extend through the turbulator body and are operative, in response to discharge of hot water from the storage tank through its outlet fitting, to receive pressurized inlet water within the dip tube and discharge the received water from a the lower end of the turbulator body in a water discharge pattern that impinges upon the lower tank end wall with substantial vertically directed and horizontally swirling force components to thereby facilitate the dislodgement of sediment from the lower tank end wall.

Abstract: The storage tank portion of a water heater has an outwardly projecting threaded pipe coupling fitting and is disposed within a jacket structure that forms an enclosed insulation space around the storage tank, the outer end of the pipe coupling fitting being spaced inwardly apart from a pipe connection opening in the jacket structure. A generally tubular foam stop member having a convexly curved side portion is positioned within the insulation space before the space is filled by an injection process with a liquid foam insulation material. The foam stop member receives the pipe coupling, is axially pressed between the storage tank and the jacket structure, and forms a seal around the pipe coupling fitting and around the jacket structure pipe connection opening.

Abstract: The external jacket structure of an electric water heater defines with the water storage tank portion thereof a hollow insulation space that horizontally circumscribes and extends across the top end of the tank. A fiberglass foam stop block member is pressed between the tank and jacket and has a cutout area through which an immersion heating element end connector is exposed to a first jacket sidewall opening normally covered by a removable access panel. A control panel mounted externally on the jacket above the first jacket sidewall opening has a bottom interior portion that downwardly overlaps a top portion of the cutout area and communicates therewith through a second jacket opening.

Abstract: The top storage tank end wall of a down-fired water heater has a first circumferentially spaced series of circular openings formed therethrough and centered about the tank axis, and a second circumferentially spaced series of circular openings centered about the tank axis and spaced radially outwardly of the first series of openings. Vertically disposed within the tank is a circumferentially spaced series of hollow U-tube immersion heating members each having a first open upper end secured to one of the first series of openings, and a second open upper end secured to one of the second series of openings. Shot-type fuel burners extend downwardly into the second open upper tube ends and are supplied with gaseous fuel via a manifold ring positioned atop the water heater. Hot combustion gases from the burners are drawn through the U-tubes by a draft inducer fan having an inlet connected to the first open upper ends of the tubes.

Abstract: A down-fired water heater has a top storage tank head portion with a central opening bordered by an upstanding annular flange. Welded within this flanged opening is a generally pan-shaped tube sheet structure having an open top side, and a bottom side wall in which a spaced pair of openings are formed. The open top ends of a U-tube immersion heating member, formed from a single length of metal tubing, are upwardly received and welded within these openings. During water heater operation, a top mounted shot-type fuel burner downwardly injects a flame, and resulting hot combustion gases, into one of the open upper ends of the U-tube. A top mounted draft inducer fan, with an inlet communicated with the interior of the tube sheet structure, draws the combustion gases through the U-tube and into the tube sheet interior via the other open tube end, and then discharges the combustion gases outwardly away from the water heater.