| 摘要 |
PURPOSE:To specify a supply of fuel gas with ease and enhance the capacity to follow even when an attempt is made to change the number of burners to be used by controlling the electric current passed to a governor proportional valve in proportion to a setting status of a combustion setting means and changing the electric current passed to said governor proportional valve to the same extent irrespective of the electric current flowing to a solenoid valve. CONSTITUTION:A control device 30 controls a combustion fan 12 and a governor proportional valve 23 in proportion to a predetermined combustion volume. A fuel gas is discharged to burners 11a and 11b from nozzles 16a and 16b. The quantity of gas is proportional to the amount of electric current flowing to the governor proportional valve 23, and is not affected by the opened/closed status of a switch over solenoid valve 24. The electric current flowing to the governor proportional valve 23 changes to the same extent irrespective of the opened/ closed status of the switch over solenoid valve 24. Therefore, when the switch over solenoid valve 24 is turned into the opened status, a supply of gas is increased by two times so that a supply of fuel may be controlled with ease. The gas is mixed with the air of the combustion fan 12, forming a predetermined combustion volume. When using two burners, one burner may be opened while the other may be closed, responding to a service condition. If the fuel gas has a large heat generation volume, the fuel can be supplied in proportion to the number of burners to be used. |
