If your carbon monoxide detector is going off, the first thing you should do is get you and your family out of the home and call the fire department.
The fire department will be able to safely get into your home and use their equipment to locate the likely source of the carbon monoxide. Unfortunately, they will shut down the gas and power to the equipment suspected of carbon monoxide leaking and red tag it. This will then leave you with no heat or hot water. The next step is contacting a licensed HVAC company to send a technician out and properly diagnose the issue. There are several different scenarios that can cause a carbon monoxide leak. We will go over a few of the most common here in this article.
Broken, Blocked, or incorrectly installed flue pipe
If your flu pipe from your furnace, boiler, or water heater is rusted, has holes (shown in the photo above), or is broken as in the photo above, it will leak carbon monoxide directly into your home. Any of those scenarios will require flu pipe replacement. The flu may also become blocked from debris buildup or even a bird or rodent. This will cause the appliance exhaust to flow back from the flu and into the home. In some cases, improper flue pipe installation will also cause an appliance to leak carbon monoxide.
Cracked or Blocked heat exchanger
A cracked heat exchanger or blocked heat exchanger such as the ones pictured above will allow carbon monoxide to leak through the cracks and pass into the blower area where it is quickly spread through the home.
If you have a high-efficiency furnace and the primary heat exchanger was found to be ok, the secondary may be where the leak is coming from. These can become blocked and crack as well. This will be easily identified by an acidic smell coming from the exhaust outside or even in the basement at the furnace.
