| 摘要 |
<p>POSITIVE AUTOMATIC DRAFT CONTROL A furnace control means is provided for reducing heat losses in the chimney stack to a minimum. The flow of air through the furnace and the flue pipe is controlled by a means to interrupt the flow of air during the period when the burner is not in operation and the usual leakage of combustion gases or the combination of such gases and air from the flue pipe to the furnace room, through the use of such means, is prevented by the use of an airtight radiator and flue pipe up to the means location.</p> |
