| 摘要 |
<p>The invention relates to a heat extractor for the recovery of heat from flue gases, such as the products of combustion from a central heating furnace, which heat extractor comprises a first impeller (2) or blower and a plurality of parallel tubes (1), around which a stream for example fresh air generated by the first impeller (2) flows in a direction transversely to the longitudinal axes (3) thereof. In the flue gases of a central heating system energy is lost as the flue gases are blown off in the free air as they still contain heat. By the use of tubes of a rectangular cross-section and a second impeller (4), which suck the flue gases through the tubes (1), the flue gases can be cooled down to room temperature.</p> |
