| 摘要 |
PURPOSE:To prevent incomplete combustion by comparing the output of intake and an exhaust fan rotational speed detection means and the output of rotational speed setting means and changing data of a drive data output means when rotational speed of the intake and exhaust fan is lower than a standard rotational speed to control the rotational speed of the intake and exhaust fan at a speed above the standard rotational speed. CONSTITUTION:A rotational speed setting means which sets in a plurality of stages the rotational speed of an intake and exhaust fan 10 corresponding to the opening of a proportional control valve 6 which represents the amount of combustion of a burner 3 is constituted of a CPU 28 and a ROM 29, and a drive data output means which outputs to a rotation drive means 27 data for driving the intake and exhaust fan 10 by the rotational speed setting means is constituted of the CPU and a RAM 30. Furthermore, data of the drive data output means is renewed by the result of comparison by the CPU 28 of the output of a rotational speed detection circuit 20 which is a detection means with the output of the rotational speed setting means. With this constitution, when the rotational speed of the intake and exhaust fan 10 drops, it is corrected, and when the rotational speed of the fan 10 rises, it is not corrected, and an amount of blast close to a set amount can be thereby secured. |
