Flue vs. Chimney — What's the Difference?

A flue is a duct, pipe, or opening in a chimney for conveying exhaust gases from a fireplace, furnace, water heater, boiler, or generator to the outdoors. Historically the term flue meant the chimney itself.

A chimney is an architectural ventilation structure made of masonry, clay or metal that isolates hot toxic exhaust gases or smoke produced by a boiler, stove, furnace, incinerator or fireplace from human living areas. Chimneys are typically vertical, or as near as possible to vertical, to ensure that the gases flow smoothly, drawing air into the combustion in what is known as the stack, or chimney effect.

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

A passage through which smoke and gases escape from a fire or furnace; a flue.

A pipe, tube, or channel for conveying hot air, gas, steam, or smoke, as from a furnace or fireplace to a chimney.

The usually vertical structure containing a chimney.

An organ pipe sounded by means of a current of air striking a lip in the side of the pipe and causing the air within to vibrate. Also called labial.

The part of such a structure that rises above a roof.

The lipped opening in such a pipe.

Chiefly British A smokestack, as of a ship or locomotive.

A fishing net.

A glass tube for enclosing the flame of a lamp.

A pipe or duct that carries gaseous combustion products away from the point of combustion (such as a furnace).

Something, such as a narrow cleft in a cliff, resembling a chimney.

An enclosed passageway in which to direct air or other gaseous current along.

A vertical tube or hollow column used to emit environmentally polluting gaseous and solid matter (including but not limited to by-products of burning carbon- or hydrocarbon-based fuels); a flue.

A woolly or downy substance; down, nap; a piece of this.

The glass flue surrounding the flame of an oil lamp.

In an organ flue pipe, the opening between the lower lip and the languet.

(British) The smokestack of a steam locomotive.

An inclosed passage way for establishing and directing a current of air, gases, etc.; an air passage

A narrow cleft in a rock face; a narrow vertical cave passage.

In an organ flue pipe, the opening between the lower lip and the languet.

A vagina.

Light down, such as rises from cotton, fur, etc.; very fine lint or hair.

A black eye; a shiner.

Flat blade-like projection on the arm of an anchor

(climbing) To negotiate a chimney (narrow vertical cave passage) by pushing against the sides with back, feet, hands, etc.

Organ pipe whose tone is produced by air passing across the sharp edge of a fissure or lip

A fireplace or hearth.

A conduit to carry off smoke

That part of a building which contains the smoke flues; esp. an upright tube or flue of brick or stone, in most cases extending through or above the roof of the building. Often used instead of chimney shaft.

A tube usually of glass, placed around a flame, as of a lamp, to create a draft, and promote combustion.

A body of ore, usually of elongated form, extending downward in a vein.

A vertical flue that provides a path through which smoke from a fire is carried away through the wall or roof of a building

A glass flue surrounding the wick of an oil lamp