What Is A Chimney Flue?
What Is A Chimney Flue?
A chimney flue is a channel connecting the interior of a building to the outside through which combustion gases, such as smoke and hot air, can be released.
Chimney flues are also known as liner, vent pipe, or smoke pipe. The material used to make chimney flues is usually metal but there are also some made of clay tile and masonry.
Properly installed chimney flues help keep the interior environment safe by preventing gas leakage into living spaces, providing an adequate ventilation for the fireplace, and ensuring that combustible materials stay away from the fire source.
Additionally, they help protect against structural damage from heat and corrosive gases.
What Is The Difference Between A Chimney And A Flue?
A chimney is a vertical structure that allows combustion gases to be safely vented out of a building.
They are commonly made from masonry and typically have an internal flue with either metal or clay liner which carries the gas up and out.
Flues, on the other hand, are essentially ducts or pipes used to carry hot air and smoke away from a fireplace, boiler, stove, water heater or any other appliance burning fuel such as wood, gas or oil.
With this in mind, the major difference between a chimney and a flue is that while a flue will typically only cover part of the way up the chimney, it is within the confines of the chimney itself.
Do All Chimneys Have A Flue?
Every wood-burning or gas fireplace has a flue. A flue is the interior passageway that routes smoke and gases from a fireplace or furnace to the exterior of the home.
The flue can be an integral part of the chimney structure and be made from brick or other masonry materials or it may be a separate piece of pipe that helps create a pathway for venting gases.
Direct-vented fireplaces, which are sealed combustion systems that pull air directly from outside without using room air for combustion, don’t require traditional flues; instead smaller exhaust pipes are installed direct to the outside.
What Does A Chimney Flue Look Like?
A chimney flue is the duct or conduit used to transport combustion gases, such as smoke, from a fireplace, furnace or water heater to the outdoors.
It is usually made of metal and lined with a material such as clay tile, cast-in-place concrete or insulation board.
The inside of the flue consists of a network of pipes and/or passageways that lead in different directions, allowing hot gases to move up through the vent system and out into the atmosphere.
Additionally, many modern chimneys come with superior draft systems which can help improve efficiency by pulling air from outside rather than from inside the home.
Across all designs though, it is important for the flue to be clean so that any dangerous buildup of creosote does not occur.
What Are The 3 Types Of Flue?
There are three main types of flue: Metallic, masonry and insulated.
- Metallic is a metal or metal-composite product that carries the products of combustion outside.
- Masonry is made up of brick, stone or concrete and also carries away the products of combustion.
- Insulated flues have an external outer casing and an internal liner which helps to reduce heat loss from the gases travelling through the flue system.
The insulating material used in this type of flue can vary depending on its application, but typically includes insulation either packed around the liner or contained within a double wall arrangement between the inner and outer layers.
How Do I Know If My Chimney Has A Flue?
To determine if your chimney has a flue, you will need to perform an inspection of the inside of the chimney equipment.
Look at the interior walls of the chimney and note whether they are smooth or lined with clay tiles. If the walls are lined with clay tiles, then it is likely that your chimney has a flue.
Additionally, check for any opening in the wall of your fireplace that leads up into the chimney – this would indicate that you have a flue installed.
You can also conduct a visual inspection from outside your home using binoculars to inspect if there is an external flue cap on top of your chimney; if one is present, this means you have a working flue installed in your chimney.
How Do You Open And Close A Chimney Flue?
It’s crucial to make sure that the fireplace is completely extinguished before closing the flue. This will prevent residual smoke and carbon monoxide from being trapped indoors and avoid burning hot surfaces.
To close the flue, you’ll need to spend a few minutes on the following steps:
- Let all surfaces cool down before proceeding.
- Use a flashlight to find the lever or pull chains, typically located on the interior front wall of the fireplace.
- If there’s a lever, move it up and down or side to side to release it and then slide it horizontally to lower the damper into the closed position. The lever should remain loose.
- For pull chains, use the longer one to release the damper and the shorter one to close the flue.
Remember to follow the reverse process to open the flue before starting your next fire.
