Furnace Chimneys and Liners

It is standard practice within the Seattle home to have the furnace checked annually. Unfortunately, most furnace inspections neglect the chimney. In order to be sure of a fully functioning Seattle chimney, it needs to be inspected through its full length. This requires it to be checked from the level of the furnace and at the roof level. Proper ventilation is imperative when working with any type of furnace. According the Chimney Safety Institute of America (CSIA) there is an average of 25,400 home fires attributed to chimneys per year and nearly 100 lives are lost annually to heating system related carbon monoxide poisonings.

The furnace chimney is a vertical ventilation system specifically designed to control air flow. The term for this Seattle chimney related air flow is draft. The pressure must allow for the fumes and gases from the furnace to rise out of the chimney while also allowing fresh Seattle air to flow into the furnace for proper combustion. Different types of furnaces will have different chimney needs and different health hazards associated with improper functioning.

There are different types of Seattle chimneys that can be built into a home. Many older Seattle homes have a masonry chimney made of brick, block, concrete, or stone. This gives the home a classic look. Over time the Seattle masonry can begin to degrade and cause the chimney to malfunction. Some of the more modern Seattle homes may have factory-built chimneys which are made of two or more layers of metal designed either with insulation between them or using air flow between the layers to act as insulation.

 

While chimneys can vary wildly, the basic Seattle chimney is composed of several parts. These parts are standard in most types of chimneys.

 

The flue is the vertical passageway up the chimney where dangerous gases pass through. In Seattle masonry chimneys it is possible to have several flues running up the chimney to each vent a different appliance such as furnace, fireplace, and stove.

 

The flue liner is a material on the inner surface of the flue that protects it and ensures the safety of the Seattle family within the home. It also makes it easier to clean the chimney and lets the furnace run more efficiently. There are different types of liners. Some liners work better for certain types of Seattle furnaces such as oil or gas. A liner is required to be up to Seattle code. Some factory-built chimneys use a stainless steel inner layer that serves as the liner.

 

The chimney crown is the top portion of the Seattle masonry chimney. It should be built on a slope toward the edge to allow Seattle rainwater to run off properly. The flue liner should extend at least two inches above the chimney crown and can often be seen from the ground.

The best time to clean a chimney is in the Seattle spring time just following the heating season. If it hasn’t been cleaned in a while, then it is best to have it inspected right away rather than waiting for the end of Seattle winter. Multiple appliances can be vented through the same chimney. These additional appliances can be used at any time of the year and can also produce dangerous gases and fire hazard.

 

The specific hazards of the chimney can be dependent on the type of appliance being used and the type of liner in the Seattle chimney. One common problem is in not updating the chimney when the furnace is updated. Proper air flow is needed to maintain safety and if the chimney is not large enough to accept all of the poisonous gases or too large to keep the proper air flow within it, carbon monoxide or other gases may escape into the home. With oil burning furnaces, the combination of carbon and sulfur produces oil soot which sits on the walls of the liner decreasing the size of the flue. Pieces of this soot can also fall back and block the flue which releases gases into the home. Gas furnaces do not have the same problem with oil soot, but a combination of moisture and high chloride content in the gases mix and deteriorates the masonry of the Seattle chimney. Flaking of the inner chimney walls not only decreases the thickness and structural integrity of the chimney but also causes a build up of brick flakes inside the chimney creating a blockage.

 

The workings of a chimney can be quite complex and it is best to have a trained Seattle professional inspect to make sure all the pieces are compatible and in working order. Some things that can be easily checked for is inspecting the chimney from the outside to see if there are any signs of cracks, missing bricks, nesting materials from Seattle birds attracted to the heat, or the liner not being visible above the chimney crown. Inside it is best to check any exposed areas of the chimney. If there is a clean-out door, you can open it to check for abundant build-up of soot, flaking bricks, sticks, or water. Also, with a mirror you can check to see if Seattle daylight is visible throughout the length of the flue. Probably the easiest check is to touch the vent while the furnace is running. It should be warm as the air is being pulled up and out of the house. If cool, it may be pulling back too much outdoor Seattle air which also allows too much of the gases to remain in the home.