The Chimney Lady

A faulty furnace or fireplace flue may cause CO backup or a chimney fire, which can be deadly. The MCSC urges homeowners to have an annual inspection of their furnace, boiler, fireplace, wood stove or water heater flue by a CSIA Certified Chimney Sweep.

Carbon Monoxide is the natural by-product of combustion of fuels.  CO is produced when gas, propane, kerosene, or wood is burned.  It is a colorless, odorless, tasteless gas that is sometimes called “The Silent Killer.”  Symptoms of CO poisoning include nausea, dizziness, disorientation,  fainting, and death.  Long-term exposure to even low levels of CO can cause irreversible brain damage, motor function impairment, and cognitive impairment.

“The most often overlooked maintenance item in the home is the furnace flue,” says Marge Padgitt, Educational Director for the MCSC.  Furnace flues clogged with debris, bird nests, fallen mortar and bricks, etc. can cause CO backup, and cracked flue tiles or missing mortar joints can cause CO leakage into the living space, which may go unnoticed by the homeowner.  It is critical that flues are in good working order and are sized correctly for the appliance in order for proper draft to occur. It is worth mentioning that most HVAC contractors do not inspect or maintain furnace flues, and that this is normally done by a chimney sweep.

 “The second most overlooked flue is the one serving a wood-burning appliance such as a wood stove or fireplace,” says Padgitt.  Many people don’t realize that creosote is flammable and needs to be removed periodically, usually once per year for a fireplace and twice per season for a wood stove. Build up of creosote can result in a chimney fire that can spread to the rest of the house.  A little-known fact is that most chimney fires go unnoticed by the homeowner and are only identified when a chimney sweep sees the flue.  Damaged flues are a fire hazard and must be relined before they are used again. 

 Tips:

•  All flues should be inspected annually and cleaned as necessary by a CSIA Certified Chimney Sweep, who is certified by the Chimney Safety Institute of America.
• Wood burning stove and fireplace stove insert flues may need to be swept twice per season to remove flammable creosote.
• ALL wood produces creosote—even dry hardwoods.
• Only burn seasoned hard or soft wood (except soft pine) in a fireplace, wood stove, or wood-burning furnace.
• Never burn trash, railroad ties, or treated wood in a fireplace or stove.  Toxic fumes can result.
• Never burn Christmas trees—they burn so fast and hot that a chimney fire will likely result.
• Furnace/hot water heater flues should be inspected annually for clogs by debris or nests, or breaks or gaps in the flue liner that could pose a Carbon Monoxide hazard.

Visit the MCSC website at http://www.mcsc-net.org for more free consumer information.

Contact Marge Padgitt, Vice-President and Educational Director, Midwest Chimney Safety Council at 816-461-3665 or e-mail margepadgitt@comcast.net for more information.

The Midwest Chimney Safety Council recommends annual inspection of all flues and chimneys serving furnaces, hot water heaters, boilers, fireplaces, wood stoves, and wood stove inserts by a professional CSIA Certified Chimney Sweep in Spring or Summer before the Fall rush.

MCSC Vice President, Marge Padgitt, says that many people are unaware of the condition of their chimney, which can be a serious problem for homeowners.  “Carbon Monoxide backup or leakage can cause the occupants to become ill or die,” says  Padgitt.  This can be caused by a faulty flue that has missing mortar joints, missing flue liner, cracks in the liner, or flues that are clogged with debris such as mortar, bricks, twigs, and bird nests.  CO problems usually arise when a gas appliance such as a furnace or hot water heater is not venting correctly.  HVAC Technicians do not inspect or maintain chimneys or flues, but professional chimney sweeps do.

Another issue is creosote accumulation from wood-burning, which is a fire hazard.  All wood produces creosote, even dry hardwoods, so an annual inspection is necessary to see if sweeping is needed and to check the chimney for cracks, holes, flammable nests, and construction issues.  Sweeping is usually done annually for flues serving fireplaces, and annually or bi-annually for flues serving wood stoves used for heating purposes. 

Chimney fires are caused by a spark, or heat above 1,000 degrees, which is the temperature that can ignite creosote.  Padgitt says that most chimney fires go unnoticed by the homeowner and are only found later by a chimney sweep.  However, if there is sufficient creosote in the flue and air for combustion, a large chimney fire can result which can lead to a house fire.  Chimney fires almost always cause damages to the flue liner and smoke chamber, and these need to be repaired before further use of the chimney.  “It is more dangerous after a chimney fire to use a damaged chimney, because creosote has more places to go between cracked flue liners and blown out mortar joints, and the next fire may be worse” said Marge.

Padgitt says that inspecting a fireplace flue properly usually requires the use of an internal video inspection camera in order to see the entire flue.  She suggests that homeowners do some research to make sure their chimney sweep uses a camera system for inspections and is Certified by the Chimney Safety Institute of America.

Visit the MCSC website at www.mcsc-net.org for more free consumer information.

Contact Marge Padgitt, Vice-President and Educational Director, Midwest Chimney Safety Council at 816-461-3665 or e-mail margepadgitt@comcast.net for more information.

Gas logs by Hargrove

By Marge Padgitt

Ventless or “non-venting” gas logs are more efficient than venting gas logs, which makes them a popular choice among consumers. However, there are some points about this type of appliance that consumers are not always made aware of before their purchase. As a service company, we have seen many issues with ventless log sets in the field after homeowners have a problem, and have first-hand knowledge of these issues.

Vent-free gas-burning log sets are advertised as being 99% efficient, which means that virtually all of the heat produced is kept in the house, rather than going out the chimney. However, this also means that the water vapor produced by the burning of gas also stays in the house- and this can be significant over a period of time. For this reason, it is my opinion that ventless logs should never be installed in a small room in a well-insulated home. Some of our customers have had mold issues caused by the excessive moisture.

The biggest complaint we receive is a strong odor when the logs are in use – at times so bad that the homeowner discontinues use of the fireplace. The source of the odor is off-gassing of items in the house such as furniture, carpet, cabinets, or chemicals like paint or bleach, which lurks in the air. In order to produce flame, the logs need oxygen, which is obtained from the air inside the house. After the chemicals are burned, they change composition and mild to strong odors may result. With venting gas logs, the odor is sent up the chimney, but with ventless logs, the odors remain in the house. 

Another issue, especially with older ventless sets is the level of Carbon Monoxide emissions. Currently, the acceptable level is 9ppm (parts per million), which means that if a log set tests at 9ppm or below, it is approved for installation in a home. Some of the sets we have tested in the field, however, are producing up to 24ppm. Notable is Dr. David Penney’s opinion that no level of CO exposure is OK for anyone, even low levels under 9ppm over a long period of time. According to Penney, it has been proven that low level exposure to CO can cause headaches, nausea, dizziness, and permanent brain damage. He suspects that CO may be a cause of Sudden Infant Death Syndrome. 

With today’s tighter, well-insulated homes, the exposure to CO is a great concern. The Environmental Protection Agency recommends a minimum of six air exchanges per day, which does not occur in many newer homes. Another issue that is complicated by tight homes is negative pressure. Negative house pressure can cause back up of flue gases from venting and non-venting gas logs and woodburning appliances, as well as furnaces and hot water heaters- which may go unnoticed by the homeowner. If testing shows negative pressure in the house a solution is to provide a whole house ventilator, such at the USPlus-Aire, which when connected to the furnace supply and return air and to the outside, provides the needed air for the home on demand whether the furnace is off or on. 

A simple test for negative pressure is to tape some newspaper strips to the front face of the fireplace during cold weather. Make sure the doors of the house are closed and all fans are off. If the paper moves outward, into the room, there is a high possibility that negative pressure is an issue. This is always worse on the lower levels of the home. Now slowly open a window and watch the paper. At the point where the paper moves back into the fireplace stop and measure the opening of the window. This is the amount of air needed to add to the house to correct the problem for that appliance only. More air will likely be needed for other appliances to function properly. Note: adding an outside air source directly to the fireplace for combustion air is not the best solution since it dumps cold air on a fire and makes it less efficient. 

Manufacturer and Code Requirements:

•  If a set is installed into a regular masonry chimney with a clay tile liner the entire chimney must be in good working order. So installation of a ventless gas log set is not a solution for a damaged chimney. 
• In most jurisdictions, ventless logs are not allowed in bedrooms. Some cities do not allow them at all. 
• Most manufacturers state that when using non-venting logs a window must be opened, which defeats the purpose of warming the house.
• Most manufacturers state that their log sets may only be used for short periods of time. 
• Never install any type of gas logs into a prefabricated or manufacturered fireplace – any alterations to this type of fireplace can cause overheating and potentially a house fire.  Check with the manufacturer first before making any changes.

Suggestions:

• If you already have a set of non-venting gas logs, read the owner’s manual thoroughly and have the set serviced at least once annually by a qualified service technician to make sure they are in good working order and CO levels are low. 
• If considering ventless gas logs, I suggest looking into Direct Vent gas inserts or freestanding stoves instead. This technology is a sealed system which uses outside air for combustion and exhausts toxic gases and moisture to the outside. Inserts can be installed into masonry chimneys and if the interior chimney is damaged it does not need to be repaired in most cases. DV inserts and stoves are high-efficiency units.
• Have the house checked for negative pressure and air exchanges, especially after insulating the home or adding thermal windows. If there is a problem, add a whole-house ventilator.

Missing mortar joints and gaps in the liner

By Marge Padgitt 

Utility flues serving furnaces, water heaters, and boilers are often forgotten and ignored, yet can pose serious hazards for the occupants of the home. Most problems lie with older masonry chimneys with clay tile flue liners, or chimneys without liners. Homeowners are generally not aware that these flues need to be inspected annually as recommended by the National Fire Protection Association 211 Standards, and that professional chimney sweeps maintain these flues. HVAC contractors do not sweep or inspect flues, or install replacement flue liners.

 Masonry chimneys deteriorate over time, starting from the interior, due to exposure to rain and acidic flue gasses, which damage mortar and clay tile liners. Over a period of years, this mortar falls and accumulates at the bottom of the flue, sometimes causing large restrictions that can cause carbon monoxide backup. Flue liners have been required by code since 1927, yet many homes built prior to 1950 do not have liners. Flue liners are installed to provide a complete sealed exit for toxic flue gases. They have mortar joints between each two-foot section of tile. But mortar joints that are deteriorated, have holes, or are missing can allow gases to escape the flue liner and enter the living space via a neighboring flue liner serving a fireplace, or through the masonry chimney.

Masonry chimneys are designed to last for many years as long as they are maintained. However, lack of homeowner education usually results in improperly maintained chimneys and flues, which can be a health hazard to the occupants and cause appliances to work inefficiently. Flue liner size is very important – and must be correct in order for draft to occur. A flue liner that is too large for the appliance may cause backup of gases. This is common in homes where newer, mid-efficiency appliances have been installed which need a smaller liner, and in cases where a high-efficiency furnace is installed and vented through the side of the house, leaving an “abandoned” hot water heater to vent on its own in a flue that is very over sized.

Carbon monoxide is an odorless, tasteless, colorless gas that is the by-product of incomplete combustion. The current standard for CO alarms is 9 ppm, however, recent testing proves that even very low levels of CO exposure over a long period of time can cause irreversible brain and organ damage. The Environmental Protection Agency states that CO detectors are to be used as a backup and are not a replacement for maintenance of appliances and flues. Even so, the EPA recommends the use of CO detectors placed strategically throughout the house.

Dr. David Penney, author of Carbon Monoxide Toxicity and professor of Physiology at Wayne State Univsersity School of Medicine has devoted years of research to this topic and posts his findings on his website at www.coheadquarters.com. Penney suggests that SIDS may be due to low level CO exposure and that children, the elderly, and pets are more susceptible to its effects.

According to the Center for Disease Control, 15,000 people visit emergency rooms and 500 people die every year due to CO poisoning. Symptoms of CO poisoning may include flu-like symptoms that go away or lessen after leaving the house, unexplained headaches, nausea, and dizziness; fainting, muscle weakness, inability to wake up, and death. If more than one family member has the same symptoms the EPA recommends visiting a doctor or hospital and mentioning that you suspect CO exposure.

Original flue was too large for the furance

Utility flue safety tips:

• Have the flue checked annually by a CSIA Certified Chimney Sweep who will look for clogs caused by bird nests, leaves, debris, dead animals, and mortar or bricks, cracked flue tiles, missing tiles, and missing mortar joints.

• Have a heavy duty stainless steel chimney cover installed to keep damaging rain and animals out of the flue.

• Make sure the flue is sized correctly to the appliances

• Never connect another appliance (water heater excepted) to the same flue as a furnace or boiler

• Have the flue examined when changing appliances

• Install CO detectors

According to a chimney sweep in Kansas City, Missouri, he has encountered numerous utility flue problems over the years, citing that it is a common issue. “People don’t think about the inside of their chimney and it is usually ignored until a chimney sweep finds a problem or someone gets ill,” stated the sweep. In one example, another chimney sweep broke out flue tiles and left them in the flue, clogging it completely, which made the homeowners very ill for weeks. In another example, over five feet of debris was removed from a boiler flue that had not been maintained for years and had blocked the flue by 90 percent. The clog caused an entire church congregation to become very ill.

 Resources:

Midwest Chimney Safety Council
Chimney Safety Institute of America
National Fire Protection Association
CO Headquarters
Environmental Protection Agency

Marge Padgitt, Education Director for the Midwest Chimney Safety Council, is available to speak to groups about chimney safety issues, appliance installation and maintenance, choosing a wood-burning appliance, chimney construction, and codes. Contact her at margepadgitt@comcast.net.