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Homeowners We hope to provide you with a better understanding of your chimney. As consumers, we do not know what we do not
know, if that makes sense. If you did fully understand your chimney, we are confident that you would have an inspection
annually. Not all chimney companies operate the same. Clearly, as in most industries, a few companies hold themselves
to higher standards and are motivated by the success and growth of the company. Not money alone. We hope our efforts
to provide homeowners the tools required to better understand their chimney, vents and/ or fireplaces will enable them to
make educated decisions and schedule routine maintenance.
The following information has been copyrighted by the Chimney Safety Institute of America. Each Public Safety Bulletin is available in brochure form. We will provide you with a copy at your request. Visit CSIA at www.csia.org for additional information.
The chimney is one of the most taken-for-granted parts of a home. Typically it tends to receive neither the attention nor the concern usually accorded other household service systems. The fact that chimneys may do their job reasonably well, even when abused or neglected, contributes to this atmosphere of indifference. Chimneys are far from the passive black holes that most people assume them to be. They perform several vital functions, and their simple appearance belies their complex construction and performance requirements. A chimney deteriorated by constant exposure to the weather can be a potential safety hazard. Weather-damaged lining system, flue obstructions and loose masonry materials all present a threat to residents. Regular chimney maintenance is essential to prevent damage, deterioration and future high cost chimney repairs. Masonry Chimneys A masonry chimney is constructed of a variety of masonry and metal materials, including brick, mortar, concrete, concrete block, stone, flue tile, steel, and cast iron. All masonry chimneys contain combinations of, or possibly all these materials, most of which are adversely affected by direct contact with water or water penetration. Water Penetration All masonry chimney construction materials, except stone, will suffer accelerated deterioration as a result of prolonged contact with water. Masonry materials deteriorate quickly when exposed to the freeze/thaw process, in which moisture that has penetrated the materials periodically freezes and expands causing undue stress. Water in the chimney also causes rust in steel and cast iron, weakening or destroying the metal parts. Note: While most stone is not affected by water penetration, large amounts or mortar are required to bond the stone together properly. Therefore, stone chimney – just like a brick chimney – should be protected from the effects of water penetration.
Water penetration can cause interior and exterior damage to your home and masonry chimney including:
Preventing Water Damage Chimney caps, also called rain covers, are probably the most inexpensive preventive measure that a home owner can employ to prevent water penetration and damage to the chimney. Chimney caps have long been recognized as an important chimney safety and damage prevention component. Underwriter’s Laboratories (UL) specifies that any chimney lining system that is to be listed to their testing standard must include a chimney cap. Chimneys have one or more large openings (flue) at the top that can collect rainwater and funnel it directly to the chimney interior. The most common flue size is 13 inches X 13 inches. An opening of that size has the potential to allow large amounts of rain or snow into the chimney during just one winter when freeze/thaw cycles are common. Chimney caps also provide other benefits. A strong, well-designed cap will prevent birds and animals from entering and nesting in the chimney. Caps also function as spark arrestors, preventing sparks from landing on the roof or other nearby combustible material. A chimney cap should be easily removable to facilitate inspection and cleaning. For a long and effective service lifetime, a cap should be constructed of sturdy, durable and corrosion resistant material. Caps may be designed to cover a single flue, multiple flues, a large portion of the chimney, or the entire chimney top. A full coverage chimney cap usually represents a larger initial investment. However, it is probably the best investment for the long-term protection because of its ability to protect the entire chimney crown. Repair or Replace a Damaged Chimney Crown The chimney crown (also referred to as the chimney wash) is the top element of a masonry chimney. It covers and seals the top of the chimney from the flue liner(s) to the chimney edge. Most masonry chimneys are built with an inadequate crown constructed from common mortar mix, the same mixture used to lay the bricks of the chimney. This mortar is not designed for and will not withstand years of weather abuse without cracking, chipping or deteriorating – situations that allow water to penetrate the chimney. In fact, most sand and mortar crowns crack almost immediately after installation because of shrinkage. A proper chimney crown should be constructed of a Portland cement-based mixture and cast or formed so it provides an overhand, or drip edge, projecting beyond all sides of the chimney by a minimum of two inches. The flue liner tile(s) should project above the crown a minimum of two inches. Waterproofing is a preventive measure. When damage or deterioration (gaps, voids, cracks, missing mortar, etc.) already exists in a masonry structure, the chimney should be repaired before the waterproofing agent is applied. A Word of Advice Your chimney system is an important part of your home heating system. For safer and more efficient operation, your chimney should be checked annually by a CSIA Certified Chimney Sweep and cleaned as needed. Each year, unsafe chimneys cause significant numbers of deaths and injuries and account for more than $200 million in property losses. Make annual chimney examinations by a CSIA Certified Chimney Sweep a regular part of your home maintenance schedule. Don’t be a statistic.
Chimney Inspections Explained for the Homeowner
Until recently, the scope of work performed in the inspection or evaluation of a fireplace, stove or other venting system was generally up to the discretion of the chimney service technician. Professional service technicians now have an industry standard that removes much of that “discretion.” The National Fire Protection Association (NFPA) has addressed the minimum chimney inspection standards in its latest publication (NFPA 211) concerning home heating appliances. Inspections are now classified as Level 1, Level 2 or Level 3. Each Level of inspection covers specific items depending on the individual appliance and venting system. Below is an explanation of the three levels of inspections and what services your chimney service technician should provide for each level. Level 1 Inspections – If your appliance or your venting system has not changed and you plan to use your system as you have in the past, then a Level 1 inspection is a minimum requirement.A Level 1 inspection is recommended for a chimney under continued service under the same conditions and with the continued use of the same appliance. In a Level 1 inspection, your chimney service technician should examine the readily accessible** portions of the chimney exterior, interior and accessible* portions of the appliance and the chimney connection. Your technician will be looking for the basic soundness of the chimney structure and flue as well as the basic appliance installation and connections. The technician will also verify the chimney is free of obstruction and combustible deposits. *Accessible: May require the use of commonly available tools to remove doors, panels or coverings, but will not damage the chimney or building structure or finish. **Readily Accessible: Exposed, or capable of being exposed, for operation, inspection, maintenance or repair without the use of tools to open or remove doors, panels or coverings. Level 2 Inspections – A Level 2 inspection is required when any changes are made to the system. Changes can include a change in the fuel type, change to the shape of, or material in, the flue (i.e. relining), or the replacement or addition of an appliance of a dissimilar type, input rating or efficiency. Additionally, a Level 2 inspection is required upon the sale or transfer of a property or after an operating malfunction or external event that is likely to have caused damage to the chimney. Building fires, chimney fires, seismic events as well as weather events are all indicators that this level of inspection is warranted. A Level 2 inspection is a more in-depth inspection than a Level 1 inspection.A Level 2 inspection includes everything in a Level 1 inspection, plus the accessible* portions of the chimney exterior and interior including attics, crawl spaces and basements. It will address proper clearances from combustibles in accessible* locations. There is no specialty tools (i.e. demolition equipment) required to open doors, panels or coverings in performing a Level 2 inspection. A Level 2 inspection shall also include a visual inspection by video scanning or other means in order to examine the internal surface and joints of all flue liners incorporated within the chimney. No removal or destruction of permanently attached portions of the chimney or building structure or finish shall be required by a Level 2 inspection. Level 3 Inspections – When a Level 1 or Level 2 inspection suggests a hidden hazard and the evaluation cannot be performed without special tools to access concealed areas of the chimney or flue, a Level 3 inspection is recommended. A Level 3 inspection addresses the proper construction and condition of concealed portions of the chimney structure and the flue. Removal or destruction, as necessary, of permanently attached portions of the chimney or building structure will be required for the completion of a Level 3 inspection.Level 3 inspection – A Level 3 inspection includes all the areas and items checked in a Level 1 and a Level 2 inspection, as well as the removal of certain components of the building or chimney where necessary. Removal of components (i.e. chimney crown, interior chimney wall) shall be required only when necessary to gain access to areas that are the subject of the inspection. When serious hazards are suspected, a Level 3 inspection may well be required to determine the condition of the chimney system. The Importance of Annual Inspections Your chimney systems are an important part of your home heating system. The National Fire Protection Association (NFPA) recommends an annual evaluation of all chimneys, fireplaces and vents. For safe and efficient operation, your chimney should be checked annually by a CSIA Certified Chimney Sweep and cleaned as needed. Each year unsafe chimneys cause significant numbers of injuries and deaths, and account for more than $200 million in property losses. Make chimney examinations a regular part of your home maintenance schedule. Don’t be a statistic.
The Importance of Flue Lining in Your Masonry Chimney
Chimneys are an integral part of most home heating systems. A masonry chimney is composed of several components, each playing an important role in the performance and function of the chimney, regardless of the fuel utilized or the heating appliance that is used. One of the most important and perhaps least understood of these components is the flue lining. This information has been produced by the Chimney Safety Institute of America (CSIA) to give the homeowner or resident a basic understanding of what a flue lining is, what function it performs, and the condition in which it should be found and maintained. Flue Lining A flue lining of a chimney is defined as “A clay, ceramic, or metal conduit installed inside of a chimney, intended to contain the combustion products, direct them to the outside atmosphere, and protect the chimney walls from heat and corrosion.” A wise homeowner will want to know about the condition of the chimney, including the flue lining, in the home he owns or plans to buy. This information can be supplied by a CSIA Certified Chimney Sweep. Although codes and building practices may vary from one state or locality to another, the installation of flue lining in chimneys has been recommended since early part of this century. It should be noted however that many chimneys built since then have not included a flue lining. Terra-cotta Flue Tile The most common material used as a lining for masonry chimneys in new construction is terra-cotta clay flue tile. It is a relatively inexpensive and easily obtainable product. Lining products made of other materials, such as ceramics, metals, and cast concrete, are also available and may be used in new construction. However, these alternatives are most commonly used in upgrading chimneys built with improper linings, those with damaged or oversized linings, or those originally built without the benefit of any type of lining. Performance Testing of Chimneys In the 1940’s and again in the 1980’s masonry chimneys were tested by the National Bureau of Standards (NBS) for durability due to rising concerns about their performance and safety. These tests involved (using clay tiles) and unlined chimneys. The published results of these studies are revealing. (1) Unlined chimneys allow heat to move through brick chimney walls very quickly. The unlined test chimney caused adjacent woodwork to catch fire after only three-and-one-half hours of testing. In fact, the unlined chimney performed so poorly that testing of unlined chimneys was abandoned. (2) Clay flue tiles were easily damaged during the testing as a result of thermal shock. All of the flue tile samples subjected to the heat shock test suffered damages in the form of cracking. (3) It was determined that if the flue gases were allowed to penetrate to the brick and mortar, the result would be a reduction in the usable life of these components due to mortar deterioration. It is important to note that flue gases are acidic in nature and can be quite corrosive. At the conclusion of the testing, the researchers recommended that flue linings, and the bonding material that joins them, be capable of containing flue gases and be designed to minimize condensation in the system. In fact, the researchers felt so strongly about the need for proper lining that they characterized building a chimney without a lining as “little less than criminal!” During all of the testing, it has been consistently shown that clay tiles crack quite easily from thermal shock. Testing has also shown that clay tile does not crack from normal usage. Thermal Shock and Liner Damage Clay tile is a ceramic product and as such it cannot rapidly absorb and evenly distribute heat during rapid temperature rises in the chimney. A rapid temperature rise (as during a chimney fire) will cause the clay material to rise in temperature much more rapidly on the inside than on the outside of the tile. As the inside heats up, it will begin to expand very rapidly, much more rapidly than the cooler outside is expanding. This uneven heating produces an unequal expansion which in turn causes the flue tile to crack and split apart. This is similar to immersing a cold drinking glass in very hot water. It will shatter instantly! Thermal shock results only during periods of rapid temperature rise or fall. These conditions are met almost solely during what is known as a chimney fire, or when water is introduced during a fire, rapidly cooling the tile. Chimney Fire Characteristics A chimney fire is defined as “combustion within the venting system of an appliance.” A venting system will include the flue, the connector pipe of a heating appliance, the thimble area (the point where the connector pipe passes into the chimney), and the smoke chamber of the fireplace (the area between the firebox and the flue). None of these areas were designed nor intended to accommodate combustion. Combustion in these areas causes temperatures to rise and heat the surrounding chimney structure quite rapidly. During a chimney fire, the flue gas temperature may well approach and at times exceed 2000 degrees Fahrenheit. This is more than enough to produce thermal shock and crack the flue tiles. A chimney fire may be either “free-burning” or may be classified as “slow-burning.” A free-burning chimney fire is what normally comes to mind when we hear the phrase “chimney fire.” Free-burning chimney fires are usually noisy and dramatic enough to be detected by the home occupants or by passers-by. These fires usually cause rumbling noises from the chimney, a tinkling sound from the connector pipe, and has even been compared to the roar of a large jet craft flying in the vicinity. Flames may be observed coming from the top of the chimney, and at times a virtual fireworks show will occur, often drawing the attention of neighbors. A slow-burning fire, on the other hand, does not always exhibit the sights and sounds commonly associated with a chimney fire. This fire burns slowly because the supply of oxygen or fuel in the venting system is limited. A slow-burning fire is potentially more damaging to the chimney and surrounding combusts tables than a free-burning fire because the areas where they occur are not venting freely. This lack of ventilation holds down obvious signs of the fire while contributing to rapid heat build-up in the chimney. When either a slow-burning or a free-burning fire has occurred, certain signs of the fire may be observed. Contrary to popular belief, a chimney fire will not always clean out a chimney. Signs that a chimney fire has occurred commonly include one or more of the following: (1) Ashes from burning creosote are usually present after a chimney fire has occurred. Creosote ash will be light-weight and fragile, with a tissue paper-like consistency. Often the creosote will exhibit many colors. (2) Clean areas may appear randomly in the flue. These clean areas are the result of extremely high heat build-up or possible air leakage into the chimney. (3) Metal chimney components such as dampers, chimney caps, or metal smoke chambers may be warped and/or discolored. Antennas mounted near chimneys may also be damaged. (4) Large pieces of expanded creosote may be found in gutters or the yard around the chimney. There may also be damage to the roof around the chimney. It is not unusual for the occupants of a home to be completely unaware that a chimney fire has occurred. Chimney sweeps find numerous cases where undetected chimney fires have occurred. Chimney fires may also occur while the occupants of the home are either asleep or away from the home. Continued use of a chimney system which has been damaged carries with it several hazards. These hazards include but are not limited to: (1) A masonry chimney expands and contracts, as it heats and cools. This may cause pieces of a cracked flue lining to fall out. As a result, the chimney becomes unlined in these areas and presents all the hazards of an unlined chimney. Fallen pieces can also block the flue and cause flue gases to back up into the appliance and the home. (2) Flue gases can leak during the use of the heating system. One of the primary functions of the flue lining is to contain these products of combustion. When a flue lining is cracked, these cracks open during the heating phase and may allow gases to pass to the chimney walls. These gases, being acidic, attack the masonry and will shorten the life of the masonry structure. In addition this can lead to carbon monoxide in the residence. (3) Heat can be transferred to the vulnerable chimney walls. One of the important functions of the flue lining is to serve as an insulator between the hot flue gases and the chimney walls. When the walls are overheated, this heat can also transfer to surrounding combustibles. Never use a chimney that does not have a liner nor has a damaged or improper lining! A Word of Advice Your chimney system is an important part of your home heating system. For safe and efficient operation, your chimney should be checked annually by a CSIA Certified Chimney Sweep and cleaned as needed. Each year, unsafe chimneys cause significant numbers of deaths and injuries and account for more that $200 million in property losses. Make chimney examinations a regular part of your home maintenance schedule. Don’t be a statistic. Chimney Safety Institute of America www.csia.org
The Facts About Chimney Fires: Cause & Cures
“Chimneys really
decorate the roofline of a home…. And they’re maintenance-free, besides. Right?” WRONG! Your chimney-and the flue that lines it-may add architectural interest to your home, but their real function is to carry dangerous fireplace, wood stove or furnace gases and smoke safely out of your home. A chimney helps your household air stay breathable… just as your windows and your bathroom, attic and kitchen vents do. Unlike those other exhaust points in your home, however, fireplace and wood stove chimneys need a special kind of care. As you snuggle in front of a cozy fire or bask in the warmth of your wood stove, you are taking part in a ritual of comfort and enjoyment handed down through the centuries. The last thing you are likely to be thinking about is the condition of your chimney. However, if you don’t give some thought to it before you light those winter fires; your enjoyment may be very short-lived. Why? Dirty chimneys can cause chimney fires, which damage structures, destroy homes and injure or kill people. No One welcomes a Chimney Fire A chimney fire in action can be impressive. It has been described variously as creating:
Creosote & Chimney Fires: What You Must Know Fireplaces and wood stoves are designed to safely contain wood-fuel fires, while providing heat for a home. The chimneys that serve them have the job of expelling the by-products of combustion – the substances produced when wood burns. These include smoke, water vapor, gases, unburned wood particles, hydrocarbon volatile, tar fog and assorted minerals. As these substances exit the fireplace of wood stove, and flow up into the relatively cooler chimney, condensation occurs. The resulting residue that sticks to the inner walls of the chimney is called creosote. Creosote is black or brown in appearance. It can be crusty and flaky…tar-like, drippy and sticky…or shiny and hardened. Often, all forms will occur in one chimney system. Whatever form it takes, creosote is highly combustible. If it builds up in sufficient quantities – and catches fire inside the chimney flue instead of the firebox of the fireplace or wood stove – the result will be a chimney fire. Although any amount of creosote can burn, sweeps are concerned when creosote builds up in sufficient quantities to sustain a long, hot, destructive chimney fire. Certain conditions encourage the build up of creosote. Simply put, restricted air supply, unseasoned wood and cooler-than-normal chimney temperatures are all factors that can accelerate the buildup of creosote on chimney flue walls. Air supplies on fireplaces may be restricted by closed glass doors or by failure to open the damper wide enough to move heated smoke up the chimney rapidly (the longer the smoke’s “residence time” in the flue, the more likely it is that creosote will form.) A wood stove’s air supply can be limited by closing down the stove damper or air inlets too soon and too much, and by improperly using the stovepipe damper to restrict air movement. Burning unseasoned wood- because so much energy is used initially just to drive off the water trapped in the cells of the logs- keeps the resulting smoke cooler, as it moves through the system, than if dried seasoned wood is used. In the case of wood stoves, fully packed loads of wood (that give large cool fires and 8 or 10 hour burn times) also contribute to creosote buildup. Cool flue temperatures speed creosote production too. Condensation of the unburned byproducts of combustion occurs more rapidly in an exterior chimney, for example, than in a chimney that runs through the center of a house and exposes only the upper reaches of the flue to the elements. How Chimney Fires Hurt Chimneys Masonry Chimneys. When chimney fires occur in masonry chimneys- whether the flues are an older, unlined type or are tile lined to meet current safety codes- the high temperatures at which they burn (around 2000°F) can “melt mortar, crack tiles, cause liners to collapse and damage the outer masonry material”. Most often, tiles crack and mortar is displaced, which provides a pathway for flames to reach the combustible wood frame of the house. One chimney fire may not harm a home. A second can burn it down. Pre-fabricated, factory-built, metal chimneys. To be installed in most jurisdictions in the United States, factory built, metal chimneys that are designed to vent wood burning stoves or pre-fabricated metal fireplaces must pass special tests determined by Underwriter’s Laboratories (UL). Most tests require the chimney to withstand flue temperatures up to 2100°F – without sustaining damage. Under chimney fire conditions, damage to these systems still may occur. When pre-fabricated, factory-built metal chimneys are damaged by a chimney fire, they should no longer be used and must be replaced. Special Effects on Wood Stoves. Wood stoves are made to contain hot fires. The connector pipes that run from the stove to the chimney are another matter. They cannot withstand the high temperatures produced during a chimney fire and can warp, buckle and even separate from the vibrations created by air turbulence during a fire. If damaged by a chimney fire, they must be replaced. Ways to Keep the Fire You Want…from Starting One You Don’t Chimney fires don’t have to happen. Here are some ways to avoid them.
Since chimney fires can occur without anyone being aware of them… and since damage from such fires can endanger a home and its occupants, how do you tell if you’ve experienced a chimney fire? Here are the signs a professional chimney sweep looks for:
Proper Maintenance Clean chimneys don’t catch fire. Make sure a CSIA Certified Chimney Sweep inspects your solid fuel venting system annually, and cleans and repairs it whenever needed. Your sweep may have other maintenance recommendations depending on how you use your fireplace or stove. CSIA recommends that you call on certified chimney sweeps, since they are regularly tested on their understanding of the complexities of chimney and venting system. What to Do if You Have a Chimney Fire If you realize a chimney fire is occurring, follow these steps:
CSIA & Certified Chimney Sweeps The Chimney Safety Institute of America (CSIA) is a non-profit educational foundation that has established the only nationally recognized certification and accreditation program for chimney sweeps in the United States. The program was developed in keeping with the CSIA’s commitment to the safety of chimney and venting systems and to the elimination of residential chimney fires, carbon monoxide intrusion and other chimney and vent-related safety hazards. The CSIA devotes its resources to educating the public, chimney service professionals and other fire prevention specialists, and the insurance industry about the prevention and correction of chimney and venting system hazards.
Safe Home Heating: Avoiding Carbon Monoxide Hazards
It’s so easy…..so automatic…. that people just don’t think about it. Every year, when the weather turns cold, homeowners reach for household thermostats, flip a switch to turn on the heat and set the temperature to 68 or 70 degrees. Little thought is given to whether the furnace exhaust system – the chimney and connector pipe – is ready to provide safe, effective service. Consumer confidence in the convenience and safety of today’s home heating systems is usually well-placed. The oil and gas heating industries have achieved impressive safety records. Nonetheless, over 200 people across the nation are known to die each year from carbon monoxide poisoning caused by problems in the venting – out of their homes – of toxic gases produced by their heating systems. This is according to statistics compiled by the U.S. Consumer Product Safety Commission. Other agencies estimate actual numbers at between 2,000 and 4,000. In addition, around 10,000 cases of carbon monoxide – related “injuries” are diagnosed each year. Because the symptoms of prolonged, low – level carbon monoxide poisoning “mimic” the systems of common winter ailments (headaches, nausea, dizziness, fatigue, and even seasonal depression), many cases are not detected until permanent, subtle damage to the brain, heart and other organs and tissues has occurred. The difficulty of diagnosis also means the numbers of people affected may be even higher. Fortunately, regular chimney system inspection and maintenance can prevent poisoning incidents like these. What Carbon Monoxide Does To You Too much carbon monoxide in your blood will kill you. Most of us know to try to avoid this. Less well known is the fact that low – level exposure to this gas also endangers your health. One of the truths of our human bodies is that, given a choice between carbon monoxide and oxygen, the protein hemoglobin in our blood will always latch on to carbon monoxide and ignore the life – giving oxygen. Because of this natural chemical affinity, our bodies – in effect – replace oxygen with carbon monoxide in our bloodstream, causing greater or lesser levels of cell suffocation depending on the intensity and duration of exposure. The side – effects that can result from this low – level exposure include permanent organ and brain damage. Infants and the elderly are more susceptible than healthy adults, as are those with anemia or heart disease. The symptoms of low – level carbon monoxide poisoning are so easily mistaken for those of the common cold, flu or exhaustion, that proper diagnosis can be delayed. Because of this, be sure to see your physician about persistent, flu like symptoms, chronic fatigue or generalized depression. If blood levels of carbon monoxide are found to be high, treatment is important. Meanwhile, it makes good sense to put heating system inspection and maintenance on your annual get – ready – for winter list. Prevention is the best cure. Causes of Heating System Problems Why is poisoning from carbon monoxide on the rise? And why does it stem primarily from home heating systems that – at first glance – seem the same as those that have been used safely for years?
When gas and oil burn in vented heating systems – in order to produce household heat – the dangerous fumes that are by – products of combustion range from soot (particulate matter) to nitrogen dioxide (also toxic) to acidic water vapors formed when moisture condenses. None of these pollutants should be allowed to leak from the chimney into your living space. In addition to carrying off toxic gases, chimneys also create the draft (flow of air) that provides the proper air and fuel mixture for efficient operation of the heating appliance – in daily use in homes throughout the country either are improperly sized or have conditions that make them unable to perform their intended function. Chimney Problems to Avoid Oil and gas furnaces have distinct burning characteristics and produce different combustion by – products. However, the chimneys and connector pipes that serve them share common problems. Both systems are subject to weathering, animal invasions, deterioration and rust – out and the accumulation of nest materials and debris. Both require care and maintenance. Oil. Oil flues need to be cleaned and inspected annually because deposits of soot may build up on the interior wall of the chimney liner. The amount of soot depends on how well – tuned the furnace is and whether the house provides sufficient air for combustion. Excessive soot causes problems that range from chimney fires… to flues back into the house and cause inefficient furnace operation. See the brochure from the CSIA specifically relating to oil – burning appliances. Gas. Natural gas is a clean – burning fuel, but today’s high – efficiency gas furnaces pose a special problem. The fumes they produce are cooler and contain high levels of water vapor, which are morel likely to cause condensation than older models. Since these vapors also contain chlorides picked up from house – supplied combustion air, the flues are subjected to more corrosive conditions than before. Even worse, many gas appliances today use chimneys that once served oil furnaces. If the liners of these chimneys are made of terra cotta (fired clay commonly used in chimney construction), bits and pieces of them slowly flake off under corrosive conditions. The combination of water – laden gas vapors available to mix with old oil soot deposits speeds this process, and debris that can block the chimney builds up at the bottom of the flue. To the extent that problems with either of these heating systems interfere with the flow of toxic gases and particles out of the house, they may also force carbon monoxide, fumes and possibly soot into the living spaces of your home. They may cause a one – time, high – level exposure situation or release smaller amounts more regularly over a longer period. These problems should never be ignored. Preventing Problems In the United States, numerous agencies and organizations now recognize the importance of annual heating system inspection and maintenance in preventing carbon monoxide poisoning. The U.S. Consumer Product Safety Commission, the U.S. Environmental Protection Agency, the National Fire Protection Association, and the American Lung Association – are some of the organizations that now encourage the regular maintenance of home heating systems and their chimneys in order to keep “the silent killer” at bay. A well – tuned furnace or boiler – connected to a venting system or flue that is correctly – sized, structurally sound, clean and free of blockages – will operate efficiently and produce a warm and comfortable home. An overlooked heating system can produce death and heartbreak. Considering the risks involved when gas or oil systems are neglected – and the benefits that accrue when they are properly maintained – you would do well to have your chimneys checked annually by a CSIA Certified Chimney Sweep®…and cleaned or repaired as needed. This can keep illness or death from carbon monoxide poisoning from claiming you or those you love.
Gas Appliance and Your Masonry Chimney
Gas in widely marked as a clean-burning fuel, and under optimum condition, that’s true. However, in order to burn the gas, your heating appliance must take in air for combustion. The same acids in the air that cause acid rain may also be present in the air your heating appliance takes in. The air may also carry chlorides – often picked up from household cleaning products or other pollution. When chlorides combine with water, hydrochloric acid is formed. Other acids may form if water mixes with residues in the flue, or with other air-borne pollutants. Water vapor is always produces during combustion. In fact, burning one cubic foot of gas yields two cubic feet of water vapor. When the heating appliance and venting system are properly matched, the water vapor is carried out of the system quickly enough and at a warm enough temperature that it does not condense inside the flue. If there is not enough heat, the water vapor will turn to liquid inside the flue. It is that acidic condensation that can deteriorate the inside of the flue. Eventually, corrosion caused by water condensing inside the flue could cause the liner to crumble. Debris from the liner could create a blockage in the chimney that could prevent carbon monoxide from leaving the system and allow it to enter your home. If the chimney is unlined or in poor condition this is especially dangerous. The Importance of Draft A proper heating appliance/venting system match will help ensure adequate draft in the system. Draft is important for a number of reasons. Inadequate draft can reduce the efficiency and safety of the appliance. Complete combustion requires oxygen – combustion of one cubic foot of natural gas requires more than 10 cubic feet of air to provide sufficient oxygen. Adequate draft ensures that enough air is pulled into the appliance for complete combustion. Incomplete combustion is also responsible for the production of carbon monoxide in the first place. If the appliance brings in the required amount of oxygen for complete combustion, carbon dioxide (CO2) is produced as a by-product. Without sufficient oxygen, carbon monoxide (CO) is produced instead. The less complete the combustion, the greater the amount of carbon monoxide produced and the less heat delivered to the home. Anything that interferes with the draft can cause more moisture to remain in the flue. Sometimes the chimney flue is too large for the appliance’s venting requirements, giving the gases more opportunity to cool and condense inside the flue. An exterior chimney, because it is cooler, will make the problem worse. The same problems can also arise if the connector pipe that joins the appliance and the chimney is too long, or if there are too many bends and elbows in the venting system. Any of these situations could allow moisture to condense inside the flue instead of being carried out of the venting system. Older, unlined chimneys are the most susceptible to corrosion partly because of their age – simply having been used for so many years. There is also a possibility that the chimney had been used to vent appliances using different fuels in the past and any soot deposits left behind by those fuels can speed up the corrosion of the chimney’s interior. Chimney flues that are unlined, oversized, or deteriorated can usually be lined with a UL listed lining system approved for gas appliances. A chimney service professional can provide more information about chimney liners. The Symptoms Although your chimney may be suffering from an improper heating/venting match without producing any visible symptoms, sometimes the excess moisture produced causes visible results. Any of the following symptoms could point to a venting system that is not matched to your heating system.
Although older chimneys are more likely to suffer, new chimneys are not impervious to the damages that can occur. Whether the chimney in your home is old or new, the National Fire Protection Association and the Chimney Safety Institute of America recommend annual evaluations of all chimneys, no matter what type of appliance they vent. There are some chimney liners that are not compatible with gas appliances because of the material from which they are made. It is important to make sure that the lining system you purchase - or even the one that may currently be in your chimney – is appropriate for use with gas appliances. Make sure that your furnace was installed according to the manufacturer’s installation instructions and the NFPA standards. The two most important NFPA standards that apply t gas appliances are NFPA 54 and NFPA211. Your appliance’s installation manual should give you all the necessary information
Care and Maintenance of Factory Built Fireplaces
Fire is one of nature’s primal forces and it has always held a special place in the live of humankind. In fact, we’ve relied on fire for so many things that it has become ingrained into our culture and lifestyle. Throughout history, fire has been crucial to human existence. Primitive people relied on fire to cook their food, to keep them warm, and to provide light. Although we no longer depend on a fire in quite the same way, images of children around campfires and holiday gatherings around an open fireplace abound. Just as our use of fire has changed over the centuries, so too have fireplaces and heating appliances that contain the fire and make it useful. In Classical Greek and Rome, homes contained simple fire pits. In Medieval Europe, simple masonry fireplaces were developed. In the 1800’s a nobleman, Count Rumford improved masonry fireplace design. In the past, fireplace and chimneys were constructed onsite as the house was built. The performance of the fireplace was often dependent upon proper construction. Today, there are factory-built fireplaces, which are pre-manufactured according to an engineered design. Proper installation, however, is still a critical factor in the safe operation of these units. Q. What is a factory-built fireplace?Unlike traditional sit-built masonry fireplaces, most factory-built fireplaces are made of metal and may use a combination of insulated walls, glass doors, air-cooled pipe and blowers to circulate the heat produced b the fire. The factory-built fireplace and chimney are a complete system engineered to work safely and efficient together. Both units (fireplace and chimney) undergo testing together, and then are listed specifically for use with each other. In other words, a factory-built fireplace has a specific chimney that is appropriate for use with that fireplace. Although models vary, factory-built fireplaces generally heat in one of two ways. With the standard radiant heat method, the heat produced by the fire radiates from the fireplace into the room. With the forced air method, which uses louvers and at least one blower, heat circulates around the walls of the fireplace and then is forced out into the room. Q. How is a factor-built fireplace different from a traditional fireplace?Because a factory-built unit is so much lighter than masonry fireplaces, these fireplaces do not require the cement foundation necessary for masonry. The installation and /or cooling spaces built into these systems allow the back of the fireplace closed to combustible materials than was previously possible. Although most units are metal, pre-manufactured masonry fireplaces are also available. These masonry models incorporate special engineering techniques that are not used in most field constructed fireplaces, including a listed venting system. Like metal factory-built fireplaces, pre-manufactured masonry fireplaces reduce the clearance to combustibles and increase the amount of heat produced by the fireplace. These advantages, coupled with the lasting nature of masonry, make pre-cast refractory fireplaces and other modular masonry fireplace systems an attractive, if somewhat more expensive, alternative to the sometimes inexpensive materials and construction of the mass-produced factory-built fireplace. Q. What’s the safest way to use a factory-built fireplace?As with any fireplace, proper use is critical to safe and efficient operation of factory-built fireplaces. When you light a fire, keep in mind the following considerations:
Q. Does a factory-built fireplace really need annual maintenance?A factory-built fireplace is tested and listed as a decorative heating appliance. This type of fireplace is relatively new to the market and has gone through many changes in design in just the past few years. The units are engineered with specific components that, when installed properly and used correctly, will give you years of enjoyable use. As homes change owners, instruction manuals can be misplaced or lost. Nearly all manufacturers will send an original instruction manual when asked. However, as time goes by, it becomes increasingly difficult to find replacement parts for the older units. Manufacturers can go out of business, complicating the problem. Regular service and maintenance will help owners keep a step ahead of potential problems. A factory-built unit will reach the end of its useful life when repairs of the unit is no longer possible, particularly if the components that are necessary to maintain the listing are no longer available. Q. How can I be sure the factory-built fireplace is installed correctly?A factory-built fireplace is the only built-in home appliance that does not require an access door or other means to monitor its condition. And it is not easily removed for inspection. However, since most problems associated with the units result from improper installation, serious consideration should be given to installing an inspection door behind the fireplace. This access will allow for an examination confirm that the system was installed according to code and can be used to track the unit’s condition as time goes on. It is an all too common occurrence to find insulation, Styrofoam, wood, tar paper, fiberglass insulation, blown or trash in contact with the fireplace or the chimney hidden from view. Fire stops must be installed. These sections of non-combustible material - generally metal - cover the opening where the chimney passes through floor or ceiling. In the event of a house fire, missing fire stops could cause fire to travel from one floor to the other, seeking oxygen. As always, reputable chimney professionals should be used when these units are purchased and installed. Local codes and the manufacturer’s installation instructions should be followed to the letter. With attention to these details, factory – built fireplaces can allow homeowners to add the warmth and glow of a fireplace to almost any part of their house for a minimal investment. Q. Where can I install a factory – built fireplace?Because metal factory – built units may be relatively lightweight and require less clearance between the fireplace and combustible materials, they afford homeowners a wide range of design and placement choices. The location of the fireplace is nearly unlimited, as long as proper clearances and venting methods are maintained. Factory – built fireplaces have been installed in bathrooms, kitchens, lofts, family rooms and living rooms. They can be installed on a sunken level, floor level or eye level. They can be flush with an exterior wall or installed on an interior wall. Q. What does a factory – built fireplace look like?Factory – built fireplaces are available in styles as varied as housing styles around the world. They can be finished with practically any material, allowing many design options. A homeowner may choose to finish the area surrounding the fireplace with a traditional full – surround mantle, painted or stained, in plain design or intricate scrollwork designs. They may choose to use a simple rough – hewn mantle of cedar or they may use stonework. The front face of the fireplace can be finished with a variety of materials, including tile or marble. Most factory–built fireplaces cone in a black finish, although many manufacturers offer them dressed with brass trim. The units are available in a wide variety of “viewing” styles also. There are the traditional single – faced units, corner units, open – ended units, three – sided units or open all around island units. Whatever designs the homeowner can imagine, factory – built fireplaces can usually fit the bill.
Annual Servicing of Oil-Fired Appliance Chimneys
Chimney Safety … because it is where you live The by-products of incomplete combustion of fuel oil are unburned carbon and sulfur - commonly called oil soot. Oil soot accumulates on the walls and at the base of the chimney. Chimneys should be inspected and serviced annually by a CSIA Certified Chimney Sweep. The best time of the year is in the springtime, after the heating season. By sweeping the chimney at this time, you don’t have to worry about a sudden cold snap interfering with the recommended annual servicing of your appliance. During the winter, the oil fired appliance is subject to long running cycles. These long run times produce oil soot that may adhere to the sides of the chimney. The accumulation of these soot deposits can fall to the base of a masonry chimney, or directly into the top of the oil fired appliance. This fallen soot build-up may restrict the flow of flue gases which consist mostly of nitrogen, carbon dioxide, sulfur dioxide and water vapor. However, the combustion process also produces carbon monoxide (a tasteless, odorless, poisonous gas). Carbon monoxide may spill back into the house instead of going up the chimney if appliances are not adequately vented or when the chimney base is not properly swept. A common misconception is that the oil service company takes care of the chimney. The reality is that the oil burner company may shovel out the base of a brick chimney and they may brush out the connector pipes, but likely will not clean the chimney system. Additionally, many oil burner service technicians may tell the homeowner that the system is okay without even inspecting the entire chimney. This includes going to the roof and inspecting the interior as well as the exterior masonry (if applicable), flashing, chimney cap, etc. The National Fire Protection Association (NFPA) 211 states that chimney shall be “inspected annually and cleaned and repaired if needed”. Just as the oil furnace is serviced annually, so should your chimney system be serviced annually by a CSIA Certified Chimney Sweep. Many homeowners are not aware that the chimney interior, when not properly maintained, will decay and break down. Failing to have an annual chimney inspection allows such decay to remain undetected – just as failing to have your teeth checked annually may allow cavities to remain undetected. What would happen if you didn’t change the motor oil in your car for 50,000 miles? Regular maintenance always pays off in the long run. The same applies with your chimney. As stated earlier in this publication, soot is comprised of carbon and sulfur. This sulfur, when mixed with rain water or moisture from the flue gases is absorbed into the flue tile and starts a deteriorating process called flaking or spalling. Just like tartar on your teeth, annual service will remove these soot deposits and keep the deterioration process to a minimum. In metal chimneys the interior lining is constructed of stainless steel, which will not rust, but can corrode from the oil soot’s sulfuric acid reaction. This corrosion causes small pinholes to form which ruin the integrity of the liner. When these pinholes form, the liner is unable to properly contain the byproducts of combustion. When a clay lining in a masonry chimney flakes, or a metal chimney or lining system corrodes, they are unable to contain the heat and the flue gases, thus create a potential hazard. When your CSIA Certified Chimney Sweep arrives at your home to perform the annual inspection and sweeping of the oil chimney, you can typically expect to see the following:
The Chimney Safety Institute of America (CSIA) is a non – profit educational foundation that has established the only nationally recognized certification and accreditation program for chimney sweeps in the United States. The program was developed in keeping with the CSIA’s commitment to the safety of chimney and venting systems and to the elimination of residential chimney fires, carbon monoxide intrusion and other chimney and vent – related safety hazards. The CSIA devotes its resources to educating the public, chimney service professionals and other fire prevention specialists, and the insurance industry about the prevention and correction of chimney and venting system hazards. For additional information, please contact: Chimney Safety
Institute of America 2155 Commercial Dr. Plainfield, IN 46168 (317) 837-5362 fax: (317) 837-5365 Email: office@csia.org Website: www.csia.org “I am very thankful for your emergency service. The gas company said I had a blocked chimney and I was to call you to have my chimney cleaned before they would turn my water back on. Your servicemen came the same day and installed a new liner. I feel much safer now…… Thank you, again.” “I like referring customers to you because you tell them when they need a liner and when they don’t….when they need any repairs for that matter...you have built good relations with many of us.” |
