| 摘要 |
<p>PROBLEM TO BE SOLVED: To detect a backflow of steam caused by leakage of a check valve in a boiler for leading out steam into a steam passage including the check valve.SOLUTION: A boiler includes: a can body 2 for leading out steam into a steam passage 7 including a check valve 8; a burner 3 for heating water in the can body 2; a water level sensor 13 for detecting a water level in the can body 2; and a pressure sensor 14 for detecting pressure in the can body 2. In a state where combustion of the burner 3 is stopped and water supply by a water pump 5 is stopped, on the basis of each of detection signals of the pressure sensor 14 and the water level sensor 13, a backflow of the steam caused by leakage of the check valve 8 is detected. Specifically, when there is a rise equal to or more than a setting in the detection water level by the water level sensor 13 after the stop of a drop of the detection pressure by the pressure sensor 14 for a preset period of time, in a state where the combustion of the burner 3 is stopped and the water supply by the water supply pump 5 is stopped, it is determined that there is a backflow.</p> |
