| 摘要 |
PURPOSE:To prevent local heating at small capacity burning, make quick switching operation of burning, and control gas pressure properly by installing one burner elements group in the middle of the other burner elements group and setting lower pressure of the former than that of the latter. CONSTITUTION:A primary burner elements group 8A which starts burning first is installed in the middle of a secondary burner elements group 8B and a setting pressure of a governor 19 is made lower than that of a gas governor 22. Thereby, even when the primary burner elements group 8A is only burning at small capacity, heat exchangers are heated uniformly and there is no anxiety of local heating. Also, when small capacity burning switched to large capacity one, flame is quickly spread from the primary burner elements group 8A to the secondary burner elements group 8B and a large amount of raw gas is prevented from being discharged. Thereby, it is made possible to control gas pressure easily by two gas governors when small capacity burning is switched to large capacity burning. |
