Carbon Monoxide and Heat Exchangers

November 02, 2018


Facts about Carbon Monoxide 

What is a heat exchanger and why is it important?
A furnace's heat exchanger is a metal component that transfers heat from the fuel being burned while preventing the air in your home from mixing with the furnace exhaust. Sometimes the heat exchanger fails, either from cracks caused by regular expansion and contraction due to heating and cooling of the metal, or from rust. When a heat exchanger fails—under certain conditions—the exhaust gases, including carbon monoxide, can combine with the air in the house. A properly running furnace should not produce significant levels of carbon monoxide; however, a cracked or leaking heat exchanger can present a safety risk.

What are the hazards correlated with a cracked heat exchanger?
A cracked heat exchanger could allow exhaust gas from the furnace to contaminate the household air with exhaust gases including carbon monoxide. In order for this to happen, the furnace must be emitting high levels of carbon monoxide and the exhaust gas must be joining with the household air. This could lead to serious illness and even death.

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What are the indicators of a cracked heat exchanger?
Apart from a visual inspection to diagnose a crack, there are a few signs of a potential complication with your heat exchanger that you may observe. If you turn the heat on and the flames flicker and appear devilish, this could be a clue that circulated air from the furnace is getting into the combustion area and you should have it checked by an HVAC technician. Although you certainly hope it doesn’t reach this point, other signs of trouble include carbon monoxide detectors sounding and you or your family members feeling sick, lightheaded or nauseous. To ensure the safety of all occupants, all homes should have a working carbon monoxide detector and batteries should be replaced frequently.

How can I be sure that my heat exchanger really has failed?
Service Experts’ NATE-certified technicians have received specialized training in diagnosing a cracked heat exchanger. As standard practice and in addition to physically observing the presence of a hole or crack, cameras are used. Whenever possible, the technician will show customers the failed heat exchanger—or at least a photo of it—so they can see for themselves. Additionally, an expert technician will test both the home and furnace for carbon monoxide. A properly functioning furnace should not generate significant levels of carbon monoxide. The technician will then warn the customers of the dangers associated with the failed part and offer professional advice regarding next steps.

What happens after an HVAC technician identifies a cracked heat exchanger?
Once you have a confirmed diagnosis from an expert, your firstquestion will likely be whether the part can be repaired or if replacement is the only option. Unfortunately, industry standard is that the heat exchanger must be replaced. In fact, the American Gas Association says that any visible crack or hole is reason for requiring replacement of the heat exchanger or furnace.

 Common sources of carbon monoxide in homes



Service Experts Heating & Air Conditioning advises changing your carbon monoxide detectors every five years and checking your carbon monoxide detectors every month to make sure the batteries and alarm are working effectively. And by keeping up with the routine maintenance of your equipment, you will have peace of mind knowing that it’s going to be safe. If you suspect a problem with your heat exchanger or need to have an analysis of carbon monoxide levels in your home, call R & M Climate Control Service Experts Heating & Air Conditioning today at 865-229-6176 or schedule an appointment online.

Tips for keeping the home safe from carbon monoxide 
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