Is Your Furnace Leaking Carbon Monoxide? Here’s How to Tell

Carbon monoxide is an odorless, colorless gas that cannot be detected by smell or sight. It is a byproduct of the incomplete combustion of fuels and can be produced by large home appliances like water heaters, gas stoves, or furnaces and boilers. Small amounts of carbon monoxide generally filter harmlessly out of the home, but an accumulation of the gas can have serious consequences. If there is a chance you’re worried about a carbon monoxide furnace leak, keep reading to learn how to stay safe.

Since you cannot see or smell carbon monoxide, it is important to check your home regularly for unsafe levels. A carbon monoxide alarm will alert you if the concentration in your home reaches an unsafe level, but a proactive approach is recommended.

With just a few quick steps, home and business owners can protect themselves against carbon monoxide poisoning.


What is Carbon Monoxide Poisoning?

Carbon monoxide (CO) is a tasteless, colorless, odorless gas found in the fumes of fuels that contain carbon, such as wood, coal and gasoline. Carbon monoxide poisoning is a potentially fatal illness that occurs when people breathe in carbon monoxide.

Once inhaled, carbon monoxide passes from your lungs into your bloodstream, where it attaches to the hemoglobin molecules that normally carry oxygen. Oxygen cannot travel on a hemoglobin molecule that already has carbon monoxide attached to it. As exposure continues, the gas hijacks more and more hemoglobin molecules, and the blood gradually loses its ability to carry enough oxygen to meet your body’s needs. Without enough oxygen, individual cells suffocate and die, especially in vital organs such as the brain and heart. Carbon monoxide also can act directly as a poison, interfering with cells’ internal chemical reactions.


Effects of Chronic Exposure to Carbon Monoxide

Chronic exposure to carbon monoxide can have extremely serious long-term effects, depending on the extent of poisoning. The section of the brain known as the hippocampus is responsible for the formation of new memories and is particularly susceptible to damage.

Up to 40% of people who have suffered from carbon monoxide poisoning experience problems such as amnesia, headaches, memory loss, personality and behavioral changes, loss of bladder and muscle control, and impaired vision and coordination. These effects do not always present themselves immediately and can occur several weeks or more after exposure. Whilst the majority of people suffering from long-term effects of carbon monoxide poisoning recover with time, some people suffer permanent effects, particularly when it comes to organ and brain damage.


What Creates Carbon Monoxide in the Home?

Carbon monoxide forms when materials burn. Homes with fuel-burning appliances have a greater likelihood of carbon monoxide leaks. Fuel-burning appliances include:

  • Clothes dryers
  • Fireplaces (gas and wood-burning)
  • Furnaces
  • Gas stoves and ovens
  • Gas-powered space heaters
  • Generators
  • Water heaters
  • Wood stoves

Cars, power tools, and lawn equipment also create carbon monoxide. If you store any of these items in an attached garage, proper storage is key to reducing the risk of the gas seeping into your home.


Is My Furnace Leaking Carbon Monoxide?

When the temperature outside starts to drop, most people crank up the thermostat. When your furnace is running constantly it can produce a significant amount of carbon monoxide. Furnaces and boilers are designed to vent this harmful gas away from the home, but an old or poorly maintained furnace can develop a leak. According to the CDC, carbon monoxide is a silent killer that takes hundreds of lives per year.

Unfortunately, you cannot tell just by looking at your furnace whether it is leaking carbon monoxide. You need a carbon monoxide detector or other special equipment to test the levels yourself. That being said, there are some signs and scenarios that might give you a clue.


Causes of Carbon Monoxide Leaks

Now that you know how to check if a furnace is leaking carbon monoxide, it is time to know what causes these leaks.

Several furnace-related problems can lead to a carbon monoxide leak. For instance, cracks in your furnace’s heat exchanger or flue pipes can allow carbon monoxide to enter your home. Also, your furnace can develop moisture in the flue pipes, leading to holes and leaks.

Faulty ductwork or a defective blower motor can be a significant issue since each can result in problems with your home’s venting, potentially welcoming carbon monoxide into your indoor air. Additionally, dirty furnace filters can lead to restricted airflow, eventually causing your furnace’s heat exchanger to overheat and crack. As a result, carbon monoxide can potentially find its way into your home’s air.


Signs That Carbon Monoxide Could Be Accumulating

  • Pilot light frequently blows out
  • Brown or yellow stains appear around the appliance
  • Smell of gas or exhaust
  • Fallen soot accumulating in the fireplace
  • Stale or stuffy air
  • Smell of something burning
  • Excessive condensation on windows around the furnace
  • Yellow burner flame rather than blue
  • Absence of upward draft in the chimney
  • Soot, smoke, or fumes coming from the chimney

The signs of carbon monoxide accumulation can be subtle, and it may take some time before you notice them. This is why it is important to know the signs of accumulation AND the early signs of carbon monoxide poisoning.


Symptoms of Carbon Monoxide Poisoning

Carbon monoxide poisoning can be particularly dangerous for people who are sleeping or intoxicated. People may have irreversible brain damage or even die before anyone realizes there’s a problem.

  • Nausea
  • Weakness
  • Shortness of breath
  • Confusion
  • Dull headache
  • Dizziness
  • Vomiting
  • Chest pain
  • Blurry vision
  • Blacking out

Prolonged exposure and lack of medical treatment may lead to serious and long-term effects and may even be life-threatening.


What To Do If You Suspect a Carbon Monoxide Leak

 If you think there is a carbon monoxide leak in your home, get people and pets out of the house and into the fresh air.

If people are experiencing symptoms, call 911. If not, contact your local fire department via a non-emergency line. The fire department has the equipment to measure gas leaks.

In fresh air, it takes 4-6 hours for a victim to clear about half of the carbon monoxide they have inhaled. The process can be accelerated with oxygen administered in a medical setting.

When it’s safe to do so, turn off the suspected gas appliance and open windows to ventilate the area. Do not use the appliance again until it’s been inspected and serviced by a certified professional.

In all cases, you’re better safe than sorry when dealing with carbon monoxide. Enlist the help of a local professional to ensure your home heating system keeps your family safe and warm through the winter.


Preventing Carbon Monoxide Poisoning

Fuel-burning products and engines produce carbon monoxide, as do some chemical products, such as paint strippers. When engines are working properly and CO-producing products are used with appropriate ventilation, they aren’t normally a cause for concern. But when an engine’s exhaust is blocked in some way, or if CO-producing products are used in a closed space, the carbon monoxide can build to dangerous levels.

Follow these recommendations to help prevent carbon monoxide poisoning:

  • Install a battery-operated or battery back-up CO alarm in the home and replace the batteries every year.
  • Place generators as far from homes as possible (minimum of 25 feet), but also at a safe distance from any nearby dwellings.
  • Never leave a car running in the garage or another enclosed space. CO can accumulate even when the garage door is open.
  • Never use a generator, grill, camp stove, or other gasoline or charcoal-burning device inside a home, basement, garage, or outside near an open window.
  • Never heat homes with a gas oven or by burning charcoal.
  • Ensure that fuel-burning space heaters are properly vented.
  • Maintain your heating system, water heater, and any gas, oil, or coal burning appliances with annual service appointments with a qualified technician.
  • Do not use portable flameless chemical heaters indoors. These types of heaters burn gas and can cause CO to build up inside your home.
  • Leave the building and dial 911 if a CO alarm sounds, if CO poisoning is suspected, or if any person begins to feel dizzy, light-headed or nauseous.
  • After a major snowstorm, your car’s exhaust pipe may be blocked by snow, causing the gas to back up into the car. To protect yourself and your passengers from carbon monoxide poisoning, avoid being in the car with the engine running when there is a risk of your tail pipe being blocked.


Final Thoughts

Chances are, you have got a perfectly safe gas furnace system and, if you have carbon monoxide detectors, you are most likely just fine. However, that does not minimize the real danger that carbon monoxide leaks pose to our customers and community. Stay smart and stay vigilant.

If your system needs repair or inspection before winter, call us on 951-926-1002. You can also visit our Contact page and complete the contact form.