Return flue

in a steam boiler, a flue which conducts flame or gases of combustion in a direction contrary to their previous movement in another flue.

See also: Return

References in periodicals archive ?
There he worked on an 1895 16 hp (some believe it to be an 18 hp) Case return flue, center-crank steam engine.
I read with interest the story in the June 2014 issue of Farm Collector, pages 30-31, pertaining to a Case center-crank return flue steam engine.
The report also boasted of the design of another product, the Stillwater engine: "The engine's return flue, being placed above the lines of the crown sheet, ensures a depth of several inches of water over it, so that it is never exposed in ascending or descending hills, and this, with the arch-like shape of the crown sheet, makes it so strong and safe that not a single instance of collapse or sagging of the crown-sheet has occurred in any one of the many hundreds of these boilers that have been and are now in use."
He claimed to have gained a 40 percent increase in fuel efficiency with the return flue compared to the straight-through flue heating system.
The company's owner, Edward Huber, earned more than 100 patents on farm machinery, including inventing the return flue boiler-type steam engine.
in addition to the first-ever return flue boiler-type steam traction engine, he invented Huber skid steam engines, Huber bean, pea and rice threshers, and much more.
In 1898, Aultman & Taylor offered Eureka Jr., Eureka and Hercules engines, as well as the straw-burning, return flue Cyclone and Columbia Jr.
Sometime between 1885 and 1900, the Phoenix return flue engine and the Star engine also appeared in the Aultman line-up.