Utility flue problems can cause carbon monoxide poisoning

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 Standard, 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 oversized. 

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 University 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.

Utility flue safety tips:

•       Have the flue checked annually by a 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

According to Gene Padgitt, owner of HearthMasters, Inc. 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,” said Gene. 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

Clogged gas flue can cause illness or death

On May 17, 2016 Blue Springs, Missouri homeowners Richard and Mary Buckley were told by their heating and cooling contractor that they needed to call a professional chimney sweep to inspect their chimney. High carbon monoxide readings indicated that something was wrong with the venting system.

When a chimney sweep arrived he found an unlined chimney in a 100-year-old home that was completely blocked with four feet of mortar, debris, leaves and twigs. The gas boiler and gas water heater could not vent toxic carbon monoxide gasses out of the flue, and it had been that way for years. The chimney sweep speculates that the only reason the homeowners were still alive is that the house is old and drafty, and that outside air diluted the toxic gasses coming into the home.

Unfortunately, the homeowners did have some symptoms of CO poisoning, which consisted of flu-like symptoms while they were inside the home, but ceased when they left the premises. This is common when a house is toxic.

According to the Midwest Chimney Safety Council, gas flues are often ignored and neglected and are commonly in much worse condition than fireplace flues. People tend to think about removing flammable creosote from a wood stove or fireplace flue, but don’t often realize that the condition of a gas flue is critical. While gas does not produce creosote, it does produce Carbon Monoxide, which must be contained within the flue walls until it exits the chimney at the top.

If the chimney is damaged or does not have a flue liner, CO can leak into the interior structure. Blockages cause CO backup, and incorrect sizing of the flue liner or connecting pipes can also be a CO hazard. Most heating and cooling contractors do not service, maintain, or repair gas flues or chimneys, and refer chimney work to professional chimney sweeps.

HearthMasters urges homeowners to have their utility flue checked annually at the same time the fireplace is serviced by a professional chimney sweep. We recommend that homeowners use a sweep who is certified by the Chimney Safety Institute of America. 

_________________

Marge Padgitt is the owner of HearthMasters, Inc. chimney and fireplace restoration and educational school in Kansas City, Missouri. www.chimkc.com 

Keep Your Fireplace in Tip Top Shape for Winter

Keep Your Fireplace in Tip Top Shape for Winter 

By Marge Padgitt, President of HearthMasters, Inc.

The following are some tips for keeping your fireplace in good order for the winter: 

•    Have all chimneys inspected annually by a professional chimney sweep to be sure they are in good working order. The sweep will inspect the interior with a chimney camera and the entire exterior wood or masonry structure visually.  He will look for cracks, gaps, or missing mortar joints in the flue, check for proper flue size, check the smoke chamber and fireplace condition, flashing, crown, and chimney cover.

•   Have flues serving wood-burning appliances swept annually or bi-annually to remove flammable creosote and reduce the risk of chimney fire. All wood creates creosote - even dry hardwoods. 

•   Have the furnace or water heater flue inspected annually by a professional to be sure it is not a Carbon Monoxide risk. Blockages or flues in poor condition can be a CO risk. Even a CO detector does not register all levels of CO. 

•   Have gas direct vent fireplaces or stoves tuned up and serviced annually to assure proper performance. Dirt, dust, and spiders clog orifices and can make the unit inoperable. Annual service is required by the manufacturer for warranty coverage on all brands.

•   Have a chimney cover installed to keep damaging rain and animals out of the flue. A cover should be installed on each flue or a custom-cover can be made to cover all flues and the cement crown.
  
•   Masonry problems such as cracked mortar or bricks, deteriorating mortar or spalling bricks should be repaired in the spring and summer months to allow for proper curing so plan accordingly.

•   Have an elastomeric sealant applied to the cement crown to protect it from weather damage. 

Carbon Monoxide Risk from Gas Chimneys Worse in Winter

By Marge Padgitt, CSIA Certified Chimney Sweep, NFI Certified Wood-burning Specialist

President, HearthMasters, Inc.

Homeowners need to be aware of the risks of Carbon Monoxide hazards with chimneys serving gas appliances. This can be a real issue when getting a home ready for rent or sale. Chimneys are the LAST thing anyone investigates, and are often overlooked when it comes to budgeting a remodel or restoration project.

 © Kheng Guan Toh

Chimneys and their flue liners and connecting pipes are designed to get toxic heated flue gasses out of the house. If a chimney is in poor condition or blocked it cannot perform its intended function, putting the occupants at risk. It is interesting to note that even with installation of CO detectors, low levels of CO (less than 9 ppm) which do not register on a detector. can cause long term health problems and even irreversible brain damage. Visit www.coheadquarters.com for more information on Carbon Monoxide symptoms, hazards, and more.

When inspecting a chimney what professional chimney sweeps look for are items that can be risks to the occupants. Among these are:

• §   Damaged or deteriorated flue liner
• §   Missing mortar joints between tile flue liner sections
• §   No flue liner installed as required by IRC code
• §   An abandoned water heater (new furnace installed, water heater is left to vent alone)
• §   Flue liner too large for the appliances to vent properly
• §   Flue liner too small for the appliances to vent properly
• §   Connecting pipes installed incorrectly
• §   No chimney cover installed to keep damaging rain, birds, and animals out of flues
• §   Debris (sand, mortar, twigs, bird nests) clogging the flue
• §   Masonry chimney in poor condition, missing mortar joints
• §   Cement crown deteriorated, cracked, or missing, allowing rain water to enter the chimney

Carbon Monoxide is odorless, tasteless, and colorless. 

During winter months when houses are closed tightly, the problem with CO becomes much worse. There is often inadequate dilution air provided so CO and other toxic gasses from off-gassing of carpet, woodwork, furniture, etc. increase in volume, making the indoor air quality worse than the rest of the year.  As a result, the occupants can experience unexplained headaches, nausea, dizziness, fainting, or death. 

If the house is under negative pressure this can exacerbate the problem. A whole house ventilator may be needed in addition to chimney repair to bringing the chimney to code and working order.

The most commont problem with chimneys serving gas appliances is rain. Rain water entering a chimney from the top through the flue or gaps in the cement crown cause mortar joints to wash out of the flue liner. Typical clay tile flue liners have mortar joints between each two-foot tile section.  Excessive condensation of flue gasses is also a major cause of missing mortar joints. This occurs when the flue liner is sized too large for the appliances and this is extremely common.

Methods of repair: There are different methods for relining, lining, or repair available. Your chimney professional is the best qualified person to address these issues and offer recommendations.

Licensing: Note that a Master Mechanical Contractor License is required to do chimney flue relining or repair in the greater Kansas City area. Check with the Johnson County Contractor Licensing website at www.jocogov.org /dept/planning-and-codes/cls/home to find a licensed contractor. 

Finding a Professional: The Chimney Safety Institute of America offers training for professional chimney technicians. The CSIA Certified Chimney Sweep designation is a minimum requirement to look for when hiring a chimney pro. Certified Chimney Sweeps know the Codes and Standards and correct methods for repair. Visit www.csia.org for more information. Additionally, request proof of liability and workers comp insurance and contractor licensing. Make sure the contractor pulls a permit for the work and it is inspected by the building inspector. Also check Angie's List for reviews. Unfortunately, there are a lot of untrained and unqualified chimney companies in existence so due diligence will pay off in the end. A mistake in this area can be deadly for occupants so it isn’t worth going the cheap or DIY route.