Relining Your Chimney Flue

A chimney flue removes harmful gases and exhausts from any fuel-burning system in and outside the home. Chimneys come in all shapes and sizes and a variety of materials. In this article, we are going to be dealing with mostly masonry and fire clay chimneys. These chimneys have the availability to vent wood-burning fireplaces or appliances. Traditionally this type of chimney is brick and mortar on the exterior, with a flue lined with terra cotta tiles. Over time, the pipes and the mortar joints that seal them together can become damaged by water, freeze-thaw, repeated thermal expansion, over-heating, acid from the exhaust, and more. These elements can lead to cracked tiles, missing mortar joints, shifted, or spalling pipes. On top of it all, the flue may never have been constructed properly in the first place. Some chimneys are built with improper materials or have no flue liner at all. 

If a flue liner in a chimney has softened, cracked, or deteriorated;

The flue no longer can contain the products of combustion, (I.e., heat moisture, creosote, and flue gases). The liner should be removed and replaced, repaired or relined with a listed system or other approved material. that will resist corrosion, softening, or cracking from flue gases at a temperature appropriate to the class of chimney service. (NFPA 211) Failed chimney flues are a severe issue. Whether it is venting your fireplace or your heating appliance, the chimney and the appliance should not be in use if the pipe is compromised. Not only is there a fire risk, but exposure to harmful gases can also occur. You should have your chimney relined if an inspection finds it necessary. These are many types of relining options. In a majority of cases, a flexible Stainless Steel (316ti or 304) Flexible liner, with a lifetime warranty, will be appropriate.

 

 

Why Reline Furnace/Water Heater/Boiler Flue?

Heat and hot water are necessities, although the risk of fire from a gas/oil appliance flue is minimal, they do pose the risk of poisonous vent gases leaking into your home. Appliance flues deteriorate at a much fast pace then fireplace flues. They are always in use, even in the summer months. The exhaust from appliances carries water vapor and acid into the pipe; this leads to erosion and corrosion of the tile and mortar joints; this can compromise the seal of the flue and the integrity of the tiles. This situation can lead to gases not venting from home. 

Relining Your Chimney Flue Increases Efficiency of Appliances

 With the increased efficiency of appliances, less heat will go into the pipe. If your tube is too large, it may not reach temperatures high enough to vent the gases properly. This problem leads to the gases cooling in the pipe and falling back into the home, called rollback. International and local codes are taking note of this, and some jurisdictions are mandating that the flue appropriately sized. Listed liners install in masonry flues any time an appliance is replaced or removed from a duct. Before changing out a device, make sure the pipe is up to code and relined with a lifetime warranty stainless steel liner, which already sized for the new appliances. Changing a chimney flue is not a project you want to find out after the fact, and not a project you want to have to do twice.