PURPOSE: To improve the durability of a combustion stack and to uniformly supply secondary air by ejecting cold air flow of a blower to burner ports and to the vicinity of the inner surface of the combustion stack through a large number of nozzle holes formed in an air ejection plate provided at the lower part of the combustion stack.
CONSTITUTION: Substantially simultaneously with starting of the combustion of a burner 23, a hot air blower 47 is actuated and external air flows into a blast chamber 46 through a suction port 48, and a blast generated by a fan 51 comes into contact with the outer surface of a combustion stack 67 and is heat-exchanged. A blast guided upwardly of a blast guide plate 76 is amalgamated with the combustion exhaust gas from the burner 23, and converted into hot air flow and discharged through a hot air discharge port 5 to carry out hot air space heating. A part of cold air blown to a blast chamber 46 is introduced into a draft chamber 64 to suppress the temperature rise of a bottom wall plate 56 and a lower plate 62. Thus, air is sent through secondary air holes 65... and blast holes 66... into a burner case 24 and a combustion stack 67, and the supply of secondary air and an operation to cool the stack 67 are carried out.
KATO HARUO
MITA SHIZUO
TOKYO SANYO ELECTRIC CO
| JPS5925048U | 1984-02-16 | |||
| JPS5316532A | 1978-02-15 | |||
| JPS55100818U | 1980-07-14 |