5 Signs Of A Cracked Furnace Heat Exchanger
The heat exchanger is an important part of a gas furnace, as this is where the air is heated before it heads into the home. Cracks in the exchanger or burner plate require immediate repair.
1. Soot Production
A crack in the heat exchanger will often lead to incomplete combustion of the fuel. When fuel doesn't fully combust, it doesn't burn cleanly and soot is produced. You will notice soot buildup on the exchanger itself, but the oily and dark-colored residue may also coat other parts of the furnace. Not only is soot messy, but it can also interfere with the operation of other parts of the furnace.
2. Yellow Flames
When operating properly, the flame in the heat exchanger should be an even, non-flickering blue. A flickering yellow flame indicates that something is wrong with the heat exchanger. It may be a minor issue, such as a dirty burner that simply needs professional cleaning, but it can also be indicative of a crack in the device that will require a more involved repair.
3. Chemical Odors
Incomplete combustion has other side effects besides soot. When the fuel doesn't fully combust, harmful gases are a byproduct. Carbon monoxide is one of these gases, which can lead to headaches, nausea, and even death. Other byproducts may produce foul odors similar to formaldehyde, which also isn't good for your health. If your carbon monoxide alarm is activating, if you are feeling unwell, or if there are chemical odors, turn off the furnace, and schedule a prompt repair visit.
4. Condensation Buildup
Generally, the complete combustion of a properly functioning heat exchanger ensures that there is no excess moisture left over as a byproduct. When the combustion is incomplete or temperatures are lower in the exchanger than they should be, condensation may develop around the exchanger and burner. If you notice moisture around or beneath the furnace, it is time to have the heat exchanger looked at.
5. Extensive Corrosion
The combination of soot, chemical byproducts, and condensation will lead to corrosion inside the furnace. Not only will this corrosion affect the heat exchanger, but it will also begin to compromise the more visible outer components on the furnace. There should never be rust or corrosion anywhere on your furnace. If you spot some, then call in a repair tech to assess the exchanger to determine if it is the cause of the problem.
Contact a furnace repair service if you suspect that something may be wrong with the heat exchanger.