| 摘要 |
<p>A thermocontact 22 arranged on the return pipe 15 of the heating water is mounted in series with a half-load resistor 21 on an electric supply phase of the extraction fan 5, so as to ensure intermittent functioning of the extraction fan when the burner is stopped, in order to avoid condensation and the untimely alarm state of the apparatus. Application to air-tight heaters.</p> |
