Signs And Causes Of Carbon Monoxide Leaks From Your Furnace | AC Repair Company | Chandler, AZ

The furnace component of your HVAC system is, in most instances, gas powered. This means that incomplete combustion of propane or natural gas in the combustion changer can produce carbon monoxide. Unfortunately, carbon monoxide is odorless and colorless. This is particularly what makes it even more dangerous. You must start noticing the signs before you notice that you have a carbon monoxide leak. Certain parts of the air conditioning system may crack or break, resulting in carbon monoxide leaks into your home. The furnace heat exchanger is one such component. This is why it is recommended that you have your HVAC system inspected and serviced by an AC repair company in Chandler, AZ. What are the signs and causes of carbon monoxide leaks in a furnace?

What’s Carbon Monoxide Poisoning?

Carbon monoxide in your HVAC is a fatal gas produced when the natural gas or propane in your furnace undergoes incomplete combustion. The gas is lighter than air and is naturally released in certain natural events like forest fires. It can be produced during an incomplete combustion of natural gases or propane in the HVAC system. Is your furnace producing a yellow flame? You should have an AC repair company inspect it. That is one sign that the natural gas is not burning properly or completely. When inhaled, this gas has severe impacts called carbon monoxide poisoning.

Signs that the Furnace is Leaking CO

Unusual Smell

Indeed, carbon monoxide doesn’t have a smell, making it virtually indictable. However, combustion spillage will emit a burning smell. Do you begin noticing a burning smell whenever you power on the furnace? That could mean you’re dealing with a gas leak. Have an AC repair company in Chandler, AZ, send someone to inspect and fix the problem. Remember, excessive flow of combustion gases could have detrimental impacts. Hence, don’t attempt DIY.


The water vapor or condensation is a by-product of combustion and indicates that the exhaust gases aren’t venting. Whenever you notice condensation around the furnace and the flame is yellow, that could mean that you might be experiencing a slow carbon monoxide leak.

Soot Mark

Incomplete combustion in the heat exchanger will result in the formation of soot. Whenever carbon doesn’t burn completely, it results in a colored (brown, black, or yellow) flaxy substance called soot. Have you seen such in your furnace? Have an AC repair company conduct further inspections.

Flame Colour

Flames from gaseous fuels should have a blue color. Does your furnace ignite in a yellow flame? It might produce a lot of carbon monoxide. An improper adjustment of the burners could cause this. What exactly does this mean? The clear blue flame indicates complete combustion. The burner supplies the necessary oxygen intake and air-fuel ratio to finish the combustion process in the burner.

In contrast, the yellow flame denotes incomplete combustion. This indicates that your appliance isn’t working properly and could generate carbon monoxide. Have you noticed this? You should have an AC repair company near you inspect your HVAC system and conduct the required repairs. This poses a significant risk. It is important to remember that some furnaces do not use these flame colors.

Heating Bill

Have you noticed a sudden increase in gas utility bills? That could mean there’s a gas leak. What will be your options in this case? You should call an AC repair company or a gas service provider and have a carbon monoxide poisoning test done to determine if there is a carbon monoxide leak. With their expertise and experience, these technicians will determine the reason for the high utility bill, and if it’s incomplete combustion or a gas leak, they will fix it.

Where Is the Carbon Monoxide Leaking From

As explained earlier, carbon monoxide is a deadly gas. Hence, it only makes sense that you want to know where the leaks are coming from. The main sources of carbon monoxide leaks in your furnace include the following:

Cracked Heat Exchanger

A thin metal barrier, a heat exchanger, separates the furnace blower and combustion chamber. The heat exchanger transfers the heat from your furnace to the ductwork distributed throughout your home. If this break, it poses a risk since it could allow carbon monoxide to seep into your home through the vents. Cracks visible upon inspection, unusual smells, worn parts, or water pooling around the furnace are all potential signs that the heat exchanger may be cracked. If you have one of these, you should immediately turn off the furnace and get in touch with an AC repair company in Chandler, AZ, to prevent carbon monoxide from seeping into your home.

Leaking Seams

The seams on your furnace or HVAC system can start leaking in different places, such as in the ductwork, and on the platform, among other points. This will result in incomplete combustion, making the air leak and carbon monoxide. If the AC repair company determines that the seams are leaking during the maintenance visit, they will patch them to prevent this problem.

Cracked Exhaust Pipes

The exhaust pipe or flue carries the by-products of combustion from the HVAC system into the atmosphere. If the exhaust pipe has a crack and there is incomplete combustion, carbon monoxide might find its way into your home. A routine air conditioning service from a reputable AC repair company can detect and fix such a problem.

Incomplete Combustion

When the flame in your furnace doesn’t get enough oxygen or combustion gases, there will be incomplete combustion. This will result in excessive carbon monoxide gas being produced. You might notice soot on the heat exchanger. When this gas escapes from a cracked heat exchanger, it could lead to carbon monoxide poisoning.

Prevent Carbon Monoxide Poisoning with a Routine Maintenance

The best way to prevent CO poisoning is through having a preventative furnace maintenance service. Do you need air conditioning service? Contact us at One Hour Air Conditioning & Heating of Phoenix.

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