LOW NITROGEN OXIDE BURNER

PURPOSE:To form the flame long and at the same time make it possible to effect two-stage combustion and suppress the generation of NOx by installing a guide plate in the gap in the lower face and side face of a burner tube which is provided with a flame hole for discharging a gas-rich mixture gas downwards with a guide plate. CONSTITUTION:On the lower face of a burner tube 6 many flame holes 10 open which jet out a gas-rich mixture gas that is supplied into a passage 8. On the other hand a guide plate 7 that covers the lower face and side face of the burner tube 6 with a gap 11 on them guides the primary flames 12 formed on the flame holes 10 and the gas unburned due to the shortage of oxygen upwards by the gap 11 and the unburned gas is made to burn by the tertiary air through a passage 15 to form secondary flames 22. Because of the combustion with shortage of oxygen the length of the primary flames 12 is large and heats the mixture gas in the burner tube 6 and the flame temperature drops. And, the secondary flames 22 extend long because of the combustion with excess air and at the same time the flame temperature is kept low by the tertiary air. Further, the combustion temperature of the flames drops also by the two-stage combustion by the flames 12 and 22. As a result it is possible to suppress the NOx generated in a gas hot-water-maker 1 to a low value.