The Chimney Sweep Company's guide to chimneys, flues and their problems...
Click on a heading to move to the section...
- How a flue works
- Flue Functions
- The smokey fire
- Primary cause of smokiness
- Secondary causes of smokiness
- Damp in flues
- Diagnosing problems
- Further sources of information
d... Flue Functions
It is also very important to understand the functions the flue is intended to perform.
For most wood and coal fires the flue has two jobs to do:
- To clear the products of combustion from the fire and to discharge them outside the building.
- To create a flow of air through the burning fire bed to provide sufficient oxygen for the efficient combustion of the fuel (this second purpose is often overlooked.)
For most gas fires however only the first above is essential. It is generally not desirable for the flue to pull air through the burner. Hence most open-flued gas fires are fitted with some form of draught breaker or diverter. (This reduces flue pull and ensures any down draught does not enter the combustion chamber and blow the flame out).