Patent ID: 9038575
Filing Date: 2015-05-26
Classification: F23D,F24H

Abstract:
1. Fuel-fired liquid heating apparatus comprising: a tank for holding a quantity of liquid to be heated, said tank having a bottom wall; a combustion chamber disposed beneath and upwardly bounded by said bottom wall; a flue communicating with said combustion chamber and extending upwardly from said bottom wall through the interior of said tank; a main fuel burner; and fuel-fired combustion apparatus operative to create hot combustion products which flow upwardly through said flue and transfer heat therethrough to liquid stored in said tank, said fuel-fired combustion apparatus comprising a pilot burner system having: a pilot fuel burner operative to create within said combustion chamber, during standby periods of said fuel-fired liquid heating apparatus, a standing pilot flame underlying a bottom surface portion of said bottom wall, and a heat concentrating structure interposed between said pilot fuel burner and said bottom surface portion of said bottom wall and having a generally vertical, open-ended passage extending therethrough and being operative to upwardly receive said standing pilot flame and concentrate its heat on said bottom surface portion of said bottom wall of said tank, wherein said heat concentrating structure comprises a generally vertically oriented tube member, having an open lower end portion and an open upper end portion, wherein the lower end portion of said generally vertically oriented tube member is positioned to receive said standing pilot flame, and wherein said lower end portion of said tube member has a lower end edge and a side wall cutout area generally facing the main fuel burner extending upwardly through said lower end edge, the side wall cutout area being arranged to allow airflow from the pilot burner to the main fuel burner for igniting the main fuel burner by means of the pilot burner.