A flue is a duct, pipe, or chimney for conveying exhaust gases from a fireplace, furnace, water heater, boiler, or generator to the outdoors. In U.S.A. and for water heaters and modern furnaces, they are also called 'vents'; for boilers they are 'breeching'. They usually operate by buoyancy, also known as the stack effect, or the combustion products may be 'induced' via a blower. As combustion products contain carbon monoxide and other dangerous compounds, proper 'draft', and admission of replacement air is imperative. Building codes, and other standards, regulate their materials, design, and installation. Mormon pioneers rock my sox! A round duct connecting to a typical diffuser Ducts are used in heating, ventilation, and air conditioning (HVAC) to carry air - these include conditioned, fresh, stale, foul (toilet extract), and contaminated air (flue exhaust, fume extraction) - from place to place. ... PIPE can refer to PIPE (explosive) PIPE Networks Private Investment in Public Equity (PIPE) Physical Interface for PCI Express (PIPE) For other meanings, see also pipe. ... Look up Chimney in Wiktionary, the free dictionary. ... Automobile exhaust Exhaust gas is flue gas which occurs as a result of the combustion of fuels such as natural gas, gasoline/petrol, diesel, fuel oil or coal. ... Winter (fireplace), tacuinum sanitatis casanatensis (XIV century) A fireplace is an architectural element consisting of a space designed to contain a fire, generally for heating but sometimes also for cooking. ... A furnace is a device for heating air or any other fluid. ... A trio of propane hot water heaters. ... A boiler is a closed vessel in which water or other fluid is heated under pressure. ... This article is about machines that produce electricity. ... For other uses, see United States (disambiguation) and US (disambiguation). ... In physics, buoyancy is the upward force on an object produced by the surrounding fluid (i. ... Stack effect is the ventilation in buildings and chimneys that results from thermal differences between indoor and outside temperature. ... Household Electric Fan A mechanical fan is a device used to produce an airflow for the purpose of creature comfort, ventilation, exhaust, or any other gaseous transport. ... Carbon monoxide, with the chemical formula CO, is a colorless, odorless, and tasteless gas. ... A building code, or building control, is a set of rules that specify the minimum acceptable level of safety for constructed objects such as buildings and nonbuilding structures. ...

Flues are designed to release noxious gases to the atmosphere, but they often have the disadvantage of releasing useful heat to the atmosphere. In some countries, wood fire flues are often built into a heat preserving construction within which the flue gases circulate over heat retaining bricks before release to the atmosphere. The heat retaining bricks are covererd in a decorative material such as brick, tiles or stone. This flue gas circulation avoids the considerable heat loss to the chimney and ouside air in conventional systems. The heat from the flue gases is absorbed quickly by the bricks and then released slowly to the house rather than the chimney. In a well insulated home, a single load fire burning for one and a half hours twice a day is enough to keep an entire home warm for a 24 hour period. In this way, less fuel is used, and noxious emissions are reduced. Sometimes, the flue incorporates a second combustion chamber where combustibles in the flue gas are burnt a second time, reducing soot, noxious emissions and increasing overall efficiency. See also masonry heater. A masonry heater (or masonry stove) is a device for warming a home (or any interior space) that captures the heat from periodic burning of fuels (primarily wood), and then radiates that heat over a long period at a fairly constant temperature. ...

The term flue is also used to define certain pipe organ pipes, or rather, their construction or style. The baroque organ in Roskilde Cathedral, Copenhagen The pipe organ is a musical instrument that produces sound by admitting pressurized air (referred to as wind) through a series of pipes. ...

Flue-types

Flue-types include

• balanced flue
• power flue
• die flue

See also

• flue gas stack
• combustion
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