| 摘要 |
PROBLEM TO BE SOLVED: To prevent the flame detecting function of a warm air heater from malfunctioning when the insulation between an electrode and the enclosure of the heater is damaged by water while the water is supplied by means of a feed pump. SOLUTION: When a sensor 44 detects that the water in a humidifying pan 40 becomes insufficient and outputs a detecting signal indicating it to a microcomputer 10, the microcomputer 10 outputs a high-level output for five seconds and the electrode 52 is energized for 5 seconds and, thereafter, the electrode 52 is repeatedly non-energized for 3 seconds and energized for 6 seconds until the sensor 44 detects that the water in the pan 40 becomes sufficient. When 5 seconds have elapsed after the detecting signal from the sensor 44 is inputted to the microcomputer 10, the microcomputer 10 controls to intermittently energize the feed pump 48 for 3 seconds and non-energize the pump 48 for 6 seconds until the sensor 44 detects that the water in the pan 40 becomes sufficient. Consequently, the electrode 53 can only be energized in the non-energizing periods of the pump 48. |
