Patent ID: 6390028
Filing Date: 2002-05-21
Classification: F23M,F23N,F24H

Abstract:
Fuel-fired liquid heating apparatus comprising:a storage tank adapted to hold liquid to be heated and having a bottom portion; a combustion chamber positioned beneath said bottom portion; fuel burning apparatus operative to combust fuel and combustion air supplied thereto from sources thereof and create hot combustion products within said combustion chamber; a control system operative to shut down said fuel burning apparatus in response to receipt of a shutdown signal; a flue extending through the interior of said storage tank and communicating with the interior of said combustion chamber; a combustion air inlet passage for delivering combustion air to said fuel burning apparatus and having an inlet portion exposed to ambient air adjacent said fuel-fired liquid heating apparatus, combustion air being deliverable to said fuel burning apparatus only via said inlet portion and through said combustion air inlet passage; and a sensor disposed externally of said combustion air inlet passage, at an elevation lower than that of said inlet portion, and being operative to sense flammable vapor and responsively transmit said shutdown signal to said control system.