Definition of flue in US English:



  • 1A duct for smoke and waste gases produced by a fire, a gas heater, a power station, or other fuel-burning installation.

    ‘no air rises up the chimney, usually because the flue is blocked’
    as modifier ‘flue gases’
    • ‘A stack thermometer installed on the stove flue will give you information on gases leaving the stove.’
    • ‘We climbed back onto our skidoos, tearing across country to a Lapp-style octagonal hut where we warmed our extremities at a roaring log fire under a central flue.’
    • ‘If central furnace/room heaters with flues are taken as the reference group, the relative risk for wall/floor heaters, both unvented and vented, is 13.’
    • ‘Vented units are designed to be permanently located next to an outside wall, so that the flue gas vent can be installed through a ceiling or directly through the wall to the outside.’
    • ‘Do not block air vents, flues or chimneys and don't have indoor fires or stoves without proper ventilation to the outdoors.’
    • ‘British Energy is seeking Government approval to install a flue gas desulphurisation system in two generating units at Eggborough power station, near Selby.’
    • ‘Don't block air vents, flues or chimneys and don't have indoor fires in rooms without ventilation.’
    • ‘Lining the flue will seal and insulate the chimney, maintaining high temperatures within the flue and preventing the smoke from condensing into soot.’
    • ‘The firm is to install flue gas desulphurisation equipment at the stations.’
    • ‘Blocked flues and chimneys stop the gas escaping - this allows it to build up in a room where it could be breathed in.’
    • ‘Six stainless steel flues vent forge smoke through the corrugated iron roof which is cut away at the ridge for a skylight that runs the length of the studio.’
    • ‘The grate or fire basket holds the flames and can be fitted with a gas burner, while the flue or chimney extracts the smoke.’
    • ‘However, Jon Goodwin, for the board, said work on items such as an extractor fan, fire door, gas flue and expansion joints was incomplete.’
    • ‘Main causes of fatal accidents are blocked or leaky flues, poor ventilation, poor installation and maintenance, faulty appliances, or misuse.’
    • ‘A crack in a fire flue was the most likely cause of that blaze, which ripped through the roof, dining room and wrecked a third of the castle on January 21.’
    • ‘In this issue Niven deals with fitting a close-coupled open vent, while David Taylor provides advice on the installation of extended flues.’
    • ‘Poor servicing or installation of appliances, inadequate ventilation or blocked flues are usually to blame.’
    • ‘The court was told that a subsequent safety check by Health and Safety officers revealed that the flue for the fire was wrongly fitted and carbon monoxide was spilling into the room.’
    • ‘However, if the damp problem has been rectified by correct installation of the stainless-steel flue, there is no need to seal the wall.’
    • ‘For the same periods, the percentage of wall, floor furnaces, and room heaters without flues has decreased from 43% to 5%.’
    duct, tube, passage, channel, canal, conduit, shaft, air passage, airway, vent, well
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    1. 1.1 A channel for conveying heat.
      • ‘As time progressed, these pots evolved into elaborate contraptions made of tin plates with flues and bends to increase heat contact, thus decreasing boiling time.’
      • ‘Older boilers send a lot of the heat they generate out of the flue into the air.’
      • ‘This design has an additional high temperature mass located at the hottest part of the flue to provide several hours of stored heat for the Stirling engine.’
      • ‘These models will have multiple flues for greater heat transfer surface, or a more submerged combustion chamber (so heat doesn't escape to the air, but is transferred to the water instead).’
      chimney, vent, shaft
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Late Middle English (denoting the mouthpiece of a hunting horn): of unknown origin. Current senses date from the late 16th century.