Abstract: A fuel-fired water heater has main and pilot burners disposed in its combustion chamber. Illustratively, all of the primary combustion air utilized by the main and pilot burners during firing thereof is supplied thereto via an enclosed path extending to the burners from outside of the combustion chamber. A burner clogging detection system is operative to shut down further combustion, upon sensing a condition of the pilot burner flame indicative of a predetermined degree of pilot burner clogging, prior to the main burner being clogged to an unacceptable degree by particulate matter entrained in incoming combustion air being delivered to the main burner.

Abstract: A fuel-fired water heater has main and pilot burners disposed in its combustion chamber. All of the primary combustion air utilized by the main and pilot burners during firing thereof is supplied thereto via an enclosed path extending to the burners from outside of the combustion chamber. A burner clogging detection system is operative to shut down further combustion, upon sensing a condition of the pilot burner flame indicative of a predetermined degree of pilot burner clogging, prior to the main burner being clogged to an unacceptable degree by particulate matter entrained in incoming combustion air being delivered to the main burner. The pilot burner may be mounted on the main burner in a variety of locations thereon.

Abstract: A radiant gas burner within the combustion chamber of a water heater has a pilot flame created using a cross-sectionally elongated raw fuel jet that impinges on an interior surface portion of a flame holding outer burner wall portion, representatively of a metal wire mesh material, and is mixed within the burner with combustion air delivered thereto from outside the combustion chamber. The resulting fuel/air mixture passes outwardly through the impinged upon mesh wall portion, which functions as a pilot flame stabilizing structure, and is ignited to form a pilot flame on the exterior of the burner body. A thermocouple portion of a clogging detection system senses a change in the pilot flame shape caused by particulate clogging of the metal mesh material and responsively terminates further gas supply to the water heater.

Abstract: A fuel-fired water heater has main and pilot burners disposed in its combustion chamber. All of the primary combustion air utilized by the main and pilot burners during firing thereof is supplied thereto via an enclosed path extending to the burners from outside of the combustion chamber. A burner clogging detection system is operative to shut down further combustion, upon sensing a condition of the pilot burner flame indicative of a predetermined degree of pilot burner clogging, prior to the main burner being clogged to an unacceptable degree by particulate matter entrained in incoming combustion air being delivered to the main burner.

Abstract: A fuel-fired low NOx water heater extending along a vertical axis has a radiant fuel burner disposed in its combustion chamber. The entire burner combustion air quantity is delivered to the burner from outside the combustion chamber via a horizontally serpentined flow path extending through an internal portion of the water heater. This serpentined air inflow path configuration causes a substantial portion of particulate matter in the incoming combustion air to be removed therefrom before entering and potentially clogging the burner.

Abstract: A radiant gas burner within the combustion chamber of a water heater has a pilot flame created using a raw fuel jet that impinges on an interior surface portion of a flame holding outer burner wall portion, representatively of a metal wire mesh material, and is mixed within the burner with combustion air delivered thereto from outside the combustion chamber. The resulting fuel/air mixture passes outwardly through the impinged upon mesh wall portion, which functions as a pilot flame stabilizing structure, and is ignited to form a pilot flame on the exterior of the burner body. A thermocouple portion of a clogging detection system senses a change in the pilot flame shape caused by particulate clogging of the metal mesh material and responsively terminates further gas supply to the water heater.