Radiant heater system

In a radiant energy heating system of the type having an energy emitting tubular conduit extending at least partly through the area to be heated, a burner connected to one end of the tubular conduit to inject thermal energy into the conduit, the other end of the conduit serving to exhaust the products of combustion from the burner wherein the improvement comprises:

• means associated with a portion of said conduit for altering the thermal output per unit length of said portion in a sense tending to match the output per unit length of at least another portion of said conduit thereby to balance the thermal emission over the length of said conduit, said means including a hollow sleeve of insulative material positioned within and concentric with the conduit wherein the thickness of the hollow sleeve of insulative material varies about the circumference of the sleeve in order that the surface of the tube immediately adjacent the thicker portion of the insulative sleeve emits a relatively lower amount of thermal energy.

In a low-intensity radiant energy heating system of the type comprising a burner, a radiating conduit of effective heating length connected to receive products of combustion from the burner and having an exhaust remote from the burner,

• a circumferentially non-uniform sleeve of insulating material within the conduit adjacent the burner and extending only through a part of the burner's effective heating length for transferring thermal energy from the conduit length nearest the burner toward the length nearest the exhaust to tend to equalize the thermal output of the conduit over its effective heating length.