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Can My Furnace Become Dangerous?

furnace-isolated-whiteThe simple answer is: yes. But we want to assure you that it is uncommon for modern residential furnaces to create hazards in a home. They are built with multiple safety features to allow them to run as safely as possible. If you are diligent about scheduling maintenance inspections and tune-ups for the furnace each fall and always respond quickly to any signs of a malfunction to call for furnace repair in Durham, NC, you should have little reason to worry about safety hazards from your gas furnace.

We still have to discuss what can go wrong, however. This will help you in case you detect signs of furnace trouble. Never hesitate to call us when you think something may be wrong (and always shut down the furnace at the furnace switch before calling us). 

Cracked Heat Exchanger

The most common cause of a furnace posing a danger to a household is a crack in the heat exchanger, which can allow toxic fumes to escape from the furnace and into the living spaces.

The heat exchanger is the metal compartment inside the furnace that gathers the hot combustion gas, then heats up and transfers the heat to the air the blower sends past it. The leftover combustion gases are safely vented through a flue. If a crack develops in the heat exchanger because of years of the metal expanding, the gases can seep out and enter the airflow. 

If you notice any signs of corrosion on the furnace or you hear a clicking noise after the blower shuts off, you may have a cracked heat exchanger. The best defense against this is annual maintenance, when our technicians inspect the heat exchanger for any damage.

Blocked Flue

The flue allows the toxic gases in the heat exchanger to escape once they’ve cooled down. The flue leads up to the roof where the gas is harmlessly released. If the flue is blocked, it may force carbon monoxide into the house. During maintenance, we also check for proper venting to ensure the toxic gases go where they are supposed to. 

If You Smell Gas or the CO Detectors Go Off… 

…don’t call us for repairs (yet)! First, shut off the gas if you have access to it and leave the house immediately. Contact the local gas company. They will come to inspect the problem and see what’s wrong. Once you can return safely to the house, that’s when you can call us to see what needs to be done about the furnace. It may need to be replaced.

Important reminder: If you use natural gas in your home in any way, you must have CO detectors installed and placed in strategic locations. Although most gas companies put a chemical into natural gas so you can smell it (a rotten egg odor), the best way to know there’s an increased level of carbon monoxide is with a detector. 

Comfort Master Heating & Air Conditioning, Inc. offers service throughout the Triangle Area of North Carolina. Call us for whatever furnace repairs you need.

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