| 摘要 |
<p>The air control is fitted to a boiler to reduce heat losses and automatically opens and closes, depending on whether the burner is operating. It comprises a fixed (17) and a mobile (18) shutter, each with air vents (23, 24) opened or closed by a sliding action. This is controlled by means of an electromagnet (25, 26) fitted to the mobile shutter and spring loaded (28) to the closed position. The boiler start control energises this magnet and opens the air vents. At the end of its stroke, a microswitch (33) is closed to initiate the burner ignition.</p> |
