Abstract: A burner head for a recuperative radiant tube burner system is constructed so as to effect clean burning of a gaseous fuel such as butane having a relatively high heat value. The burner head includes a sleeve having a frustoconical section formed with combustion air ports which cause combustion air to spin and mix thoroughly with butane discharged from a gas nozzle having a discharge orifice located downstream of certain ones of the combustion air ports.

Abstract: A recuperative radiant tube heating system in which a recuperator tube telescoped into a radiant tube and over a burner assembly is formed as three interconnected sections to facilitate manufacture of the recuperator tube, to facilitate assembly of the recuperator tube with the burner head of the burner assembly and to enable easy replacement of that portion of the recuperator tube which is most susceptible to burn out. The burner head includes a nozzle having gas discharge ports which are angled in such a manner as to effect good mixing of the gas with combustion air while reducing the likelihood of the ports becoming clogged with carbon.

Abstract: A burner assembly for heating a U-shaped radiant tube. The burner assembly includes a generally conical burner nozzle supported on the end of a gas supply pipe and disposed within an inner tube which, in turn, is located within the radiant tube. The burner nozzle may be adjusted selectively back and forth within the inner tube to change the ratio of primary and secondary combustion air supplied to the nozzle and thereby change the length of the flame produced by the burner assembly.

Abstract: A single-ended recuperative radiant tube assembly for increasing the efficiency of a combustion furnace system by using less fuel input per heat output than conventional systems. The single-ended recuperative radiant tube assembly has inner and outer recuperator tube assemblies positioned in a counterflow arrangement within a radiant tube assembly. Hot exhaust gases emitted from a burner within the single-ended radiant tube assembly are directed through a flame tube to an annular exhaust chamber located between the outer recuperator tube and radiant tube assemblies. Ambient air flowing towards the burner in an air chamber between the inner and outer recuperator tube assemblies is heated by the exhaust gases in the annular exhaust chamber.

Abstract: An internal plug-in recuperator positioned within the exhaust assembly of a furnace for increasing the efficiency of a combustion furnace system by using less fuel input per heat output than conventional systems. Hot exhaust gases flowing within the exhaust assembly heat ambient air are directed through the recuperator before that air is injected into the burner. Preferably, the recuperator is constructed in a counterflow arrangement with an inner recuperator tube positioned within an outer recuperator tube.