Flue definition
A combustion appliance is an apparatus in which fuel is burned to generate heat for space heating, water heating, cooking or other similar purposes.
A flue is a passage that conveys the products of combustion from a combustion appliance to the outside air.
A fluepipe is a pipe, either single walled (bare or insulated) or double walled, which connects a combustion appliance to a flue in a chimney. When used in this way, it may be called a connecting fluepipe.
A flue 'throat' is a contracted part of a flue between a fireplace recess and its chimney.
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