Combustion apparatus

A combustion apparatus, comprising:

• a combustion housing;
• a partition plate provided in the combustion housing to partition a space in the combustion housing into a combustion chamber and an air supply chamber on a lower side of the combustion chamber;
• a plurality of rich-lean burners arranged in a right-left direction of the combustion chamber, each of the rich-lean burners including a burner main body elongated in a front-rear direction thereof, a lean flame port jetting out a lean mixture gas of a fuel concentration leaner than a theoretical air fuel ratio, and a couple of rich flame ports situated on both sides of the lean flame port in a right-left direction thereof to jet out a rich mixture gas of a fuel concentration richer than that of the lean mixture gas, the lean flame port and the rich flame ports situated at an upper end of the burner main body;
• a multiplicity of distributed holes formed in the partition plate through which distributed holes secondary air is supplied from the air supply chamber to the combustion chamber;
• a flame rod facing to an upper side of a part of the rich-lean burners to stop combustion when the flame rod does not detect any flames owing to a flame lift at a time of an oxygen deficiency,
• wherein a supply quantity of the secondary air to the part of the rich-lean burners to which part the flame rod faces is larger than those to other parts.