Abstract: A gas fired furnace capable of operating with a 16:1 turndown ratio or greater. The furnace includes a plurality of burners (10) grouped into at least (14a) first and second (14b) groups, each group connected to a source of combustible gas through a control valve (30a, 30b, 30c). The control valve (30c) controlling at least one group of burners is of a modulating type having an output proportional to a control signal applied to the valve. The burners fire into associated heat exchange tubes (20a), each tube having an inlet (24) and an outlet. The tube outlets are connected to a collector chamber (44) that includes a baffle plate (60) that divides the collector into two sections, one of the sections communicating with the outlets of the tubes associated with the first group of burners, the other section communicating with the outlets of the heat exchanger tubes associated with the other group of burners.

Abstract: A gas burner for a gas fired heating appliance, such as a water heater. The gas burner is located within a combustion chamber and includes an inlet conduit through which combustible gas and primary air are received. An air scoop shrouds the inlet conduit and at least partially defines a flow path of primary air, substantially isolated from the combustion chamber and which extends from the inlet end of the inlet conduit to a primary air port that communicates with a source of primary air located outside the combustion chamber. The combustion chamber also includes at least one port through which secondary combustion air is admitted into the combustion chamber. A flow path transition member is located within the combustion chamber and is in fluid communication with the primary air port. The transition member also forms part of the isolated primary air flow path and sealingly engages the air scoop when the burner is installed into the combustion chamber.

Abstract: A heat exchanger tube having an integral restricting and turbulating structure consisting of dimples formed by confronting indentations pressed into the sides of the heat exchanger tube. The dimples are comprised of indentations disposed in pairs which extend into the tube to such a depth as is necessary to significantly reduce the cross sectional area of the heat exchanger tube and provide a pair of converging, diverging flow nozzles to promote turbulence of the flue gases. The turbulence characteristics of the tube can be controlled by varying the size of the aperture of the nozzles. In certain applications, the dimples are located along the sides of the heat exchanger tube, thereby providing unobstructed drainage for liquids even when the tube is bent into a serpentine shape.

Abstract: A method and apparatus for sealing the end of a burner tube including the step of forming a bore near the end of the burner tube and inserting a cone-shaped plug element into the bore until a circular periphery of the plug element abuttably engages a step defined by the stepped bore. The circular periphery of the plug element has a diameter that is greater than an inside diameter of the step formed by the stepped bore. A force is then applied to the plug element tending to cause its circular periphery to expand radially outwardly until the circular periphery sealingly engages the inside of the stepped bore. The sealing method and apparatus allows various processing steps to be performed on the tube, such as bending, drilling, painting and punching to be performed prior to sealing the end of the tube.

Abstract: A burner having an elongate, generally tubular sheet metal body having an inlet end, a closed distal end and a tubular segment extending between the ends. The inlet end is formed to define a gas orifice holder which is adapted to mount a gas orifice element. The inlet end is further formed to define at least one primary air opening arranged to admit primary air from a source of primary air. Rows of flame ports are defined in the tubular segment and are arranged to create a desired predetermined flame pattern. When used as a fireplace burner the flame ports may be slot-like in construction and include tabs which determine the effective size of the ports. In a fireplace application, flame ports located below a crossover log, are eliminated and/or formed of reduced size, thus providing a flame of lower height and/or less intensity, thus substantially eliminating sooting.

Abstract: A heat exchanger tube having an integral restricting and turbulating structure consisting of dimples formed by confronting indentations pressed into the sides of the heat exchanger tube. The dimples are comprised of indentations disposed in pairs which extend into the tube to such a depth as is necessary to significantly reduce the cross sectional area of the heat exchanger tube and provide a pair of converging, diverging flow nozzles to promote turbulence of the flue gases. The turbulence characteristics of the tube can be controlled by varying the size of the aperture of the nozzles. In certain applications, the dimples are located along the sides of the heat exchanger tube, thereby providing unobstructed drainage for liquids even when the tube is bent into a serpentine shape.

Abstract: A heat exchanger tube having an integral restricting and turbulating structure consisting of dimples formed by confronting indentations pressed into the sides of the heat exchanger tube. The dimples are comprised of indentations disposed in pairs which extend into the tube to such a depth as is necessary to significantly reduce the cross sectional area of the heat exchanger tube and provide a pair of converging, diverging flow nozzles to promote turbulence of the flue gases. The turbulence characteristics of the tube can be controlled by varying the size of the aperture of the nozzles. In certain applications, the dimples are located along the sides of the heat exchanger tube, thereby providing unobstructed drainage for liquids even when the tube is bent into a serpentine shape.

Abstract: Apparatus and method for producing bends in tubes, including a bending die assembly having a fixed die section that is rigidly mounted to a support member and at least one a movable die section that is movable relative to the fixed section. When used to make “wrinkle” bends the die assembly includes a pair of moveable die section that are moveable relative to the fixed die section and relative to each other along a predetermined path. The movable die section or sections are supported for movement in a common plane and include camming pins engageable with slots formed in the support member, such that the engagement of the pins with the associated slots define paths of movement for the die sections. When used to make “wrinkle” bends, the fixed die section and movable die sections define wrinkle receiving recesses.

Abstract: Apparatus and method for producing bends in tubes, including a bending die assembly having a fixed die section that is rigidly mounted to a support member and at least one a movable die section that is movable relative to the fixed section. When used to make “wrinkle” bends the die assembly includes a pair of moveable die section that are moveable relative to the fixed die section and relative to each other along a predetermined path. The movable die section or sections are supported for movement in a common plane and include camming pins engageable with slots formed in the support member, such that the engagement of the pins with the associated slots define paths of movement for the die sections. When used to make “wrinkle” bends, the fixed die section and movable die sections define wrinkle receiving recesses.

Abstract: A heat exchanger tube having an integral restricting and turbulating structure consisting of dimples formed by confronting indentations pressed into the sides of the heat exchanger tube. The dimples are comprised of indentations disposed in pairs which extend into the tube to such a depth as is necessary to significantly reduce the cross sectional area of the heat exchanger tube and provide a pair of converging, diverging flow nozzles to promote turbulence of the flue gases. The turbulence characteristics of the tube can be controlled by varying the size of the aperture of the nozzles. In certain applications, the dimples are located along the sides of the heat exchanger tube, thereby providing unobstructed drainage for liquids even when the tube is bent into a serpentine shape.

Abstract: A burner nozzle includes a burner tube that extends along a central axis and has an inlet end portion for receiving combustible gas and air. The burner tube extends along the central axis from the inlet end portion to an outlet end portion for releasing a mixture of gas and air. A curved head with a plurality of openings and an imperforate portion is connected to the outlet end portion. The openings and imperforate portion of the curved head create a transverse flow of gas and air out of the curved head to produce a shaped flame. A burner assembly may include a combustion tube in which the burner nozzle is disposed and connected. The burner nozzle is used in a method of widening and shaping a flame.

Abstract: A burner having an elongate, generally tubular sheet metal body having an inlet end, a closed distal end and a tubular segment extending between the ends. The inlet end is formed to define a gas orifice holder which is adapted to mount a gas orifice element. The inlet end is further formed to define at least one primary air opening arranged to admit primary air from a source of primary air. A bluff body is located downstream from the gas orifice element and is positioned such that gas emitted by the orifice impinges on the bluff body. Rows of flame ports are defined in the tubular segment and are arranged to create a desired predetermined flame pattern. When used as a fireplace burner the flame ports may be slot-like in construction and include tabs which determine the effective size of the ports.

Abstract: A gas burner that produces a yellow flame for use in a fireplace assembly, including front and rear non-combustible logs and a cross-over log supported atop the front and rear logs. The burner includes an elongate, generally tubular sheet metal body having an inlet end, a closed distal end and a tubular segment extending between the ends. The inlet end is formed to define a gas orifice holder which is adapted to mount a gas orifice element and to define at least one primary air opening arranged to admit combustion air into the tubular burner segment. A bluff body is located downstream from the gas orifice element and is positioned such that gas emitted by the orifice impinges on the bluff body. Rows of slot-like flame ports are defined in the tubular segment and are arranged to create a desired predetermined flame pattern and include tabs which determine the effective size of the ports.

Abstract: A gas burner is disclosed. The gas burner includes a burner body including a pair of adjoining metal stampings that form a serially connected gas supply passage, venturi region, and plenum chamber, the gas supply passage defining at least one air supply hole for introducing air into the gas supply passage. A burner port is defined by integrally formed recesses in each adjoining metal stamping, the burner port being in fluid communication with the plenum chamber and being oriented about 90 degrees with respect to the central axis of the burner. The gas burner is fabricated from a pair of adjoining sheet metal halves. An alternate gas burner includes a tapered burner port which provides a more uniform flame height because it compensates for velocity variations in the flowing air fuel mixture. A divider plate is also included in the port which improves flame stability.

Abstract: A heat exchanger tube having an integral restricting and turbulating structure consisting of dimples formed by confronting indentations pressed into the sides of the heat exchanger tube. The dimples are comprised of indentations disposed in pairs which extend into the tube to such a depth as is necessary to significantly reduce the cross sectional area of the heat exchanger tube and provide a pair of converging, diverging flow nozzles to promote turbulence of the flue gases. The turbulence characteristics of the tube can be controlled by varying the size of the aperture of the nozzles. In certain applications, the dimples are located along the sides of the heat exchanger tube, thereby providing unobstructed drainage for liquids even when the tube is bent into a serpentine shape.

Abstract: The inventive burner can receive air and fuel and discharge a fuel/air mixture for combustion at a periphery of the burner while limiting NOx emissions. The burner has a central axis and includes first and second plates constructed and arranged so as to form between them a central chamber and a plurality of burner ports extending outwardly of the chamber. The first and second plates have an outer periphery spaced outwardly from the central axis. The second plate indudes an opening for receiving the air and fuel into the chamber. The outer periphery of the second plate extends from the central axis by a greater distance than the outer periphery of the first plate. The second plate has an outer peripheral portion in which a plurality of openings may be formed. Also included is a method for operating the burner so as to limit NOx emissions.

Abstract: A burner nozzle includes a burner tube that extends along a central axis and has an inlet end portion for receiving combustible gas and air. At least one body or chamber has a passageway in communication with the burner tube along the central axis which leads to an elongated outlet end portion. At least one flame-shaping opening is located adjacent the outlet end portion. Each flame-shaping opening may be constructed and arranged effective to elongate (broaden the width of) flame resulting from combustion of the mixture transverse to the central axis to produce efficient heat transfer between the flame and air inside a heat-receiving member disposed downstream of the outlet opening. A flame length reducing member may be used instead of or in addition to the flame-shaping opening and the flame shaping opening may itself reduce flame length. A burner assembly may include a combustion tube in which the burner nozzle is disposed and connected.

Abstract: A gas burner produces a homogeneous mixture of gas and air in a short mixing zone by creating turbulence to promote thorough mixing. The burner includes a burner housing supporting a gas distribution tube and an air blower, the distribution tube emitting jets of gas in a radial direction and supporting a baffle plate having a plurality of openings. Air from the blower impinges on the jets of gas to form streams of gas and air that pass through the openings in the baffle plate. A diffuser ring is disposed downstream from the baffle plate and extends radially inward to form a flow constriction. The streams of gas and air contact the diffuser ring and undergo turbulence and the resulting mixture of gas and air passes through the diffuser ring and expands within the interior of a perforated combustion head. The mixture passes through the perforations and when ignited obtains combustion of nearly 100% of the gas and produces a very even flame profile.

Abstract: An inshot gas burner nozzle having a flame retention insert that enhances flame stability and reduces noise, the insert comprising a central opening, secondary openings of smaller diameter arranged circularly around the central insert, and a plurality of restricted peripheral openings in the form of stepped notches. The nozzle further comprises plenum chambers which have restricted outlets thereby creating back pressure within the plenums to improve cross-ignition of adjacent nozzles.