Patent ID: 6766771
Filing Date: 2004-07-27
Classification: F23N,F24H

Abstract:
A fuel-fired heating appliance comprising:a combustion chamber; a burner disposed in said combustion chamber and operative to burn received fuel and combustion air and responsively create hot combustion products in said combustion chamber; a flue extending from said combustion chamber and operative to receive said hot combustion products, said flue having an outlet; a draft structure coupled to said flue outlet and including a vent pipe, said draft structure being operative to create a draft through said flue to facilitate discharge of combustion products from said flue outlet and through said vent pipe; and cutoff apparatus operative to sense a parameter of hot combustion products traversing said draft structure and, in response to a predetermined magnitude of said parameter, prevent both (1) the creation of a predetermined, unacceptably high level of carbon monoxide in said combustion chamber, and (2) thermal damage to said vent pipe caused by an unacceptably high temperature of combustion products traversing said draft structure, by terminating further firing of said heating appliance, said magnitude of said parameter being correlated in a predetermined manner to both the level of carbon monoxide in said combustion chamber and said unacceptably high temperature of combustion products traversing said draft structure.