PURPOSE: To provide a water level controller capable of not only controlling water level but also detecting fault and the leakage of water by using two water level sensors.
CONSTITUTION: By the upper water level sensor 54 and the lower water level sensor 55, the quantity of water in a water storage tank 5 is detected. It does not occur physically that both of the upper water level sensor 54 and the lower water level sensor 55 detect simultaneously a ball, therefore it is decided that on of the upper water level sensor 54 and the lower water level sensor 55 is abnormal. It does not occur physically that the upper water level sensor 54 detects water and the lower water level sensor 55 does not detect water, therefore it is decided to be a fault. In the case water decreases in spite of a fact that a flow solenoid valve 43 is not operating, it is decided to be abnormal in leakage of water. In the case the upper water level sensor 54 cannot detect the ball even if a prescribed time elapses, after an operation of a water supply solenoid valve 34, it is considered to be a fault of the upper water level sensor 54 or suspension of water supply, therefore it is decided to be abnormal.
YAJIMA TAKEO
NIWAYAMA AKIRA
YAMAMOTO ISAO
SUDO SUSUMU
MITSUIDA MASAO
HIRAKATA HARUO
FUKAZAWA AYANORI
