The heat exchanger in your heating system heats the air in your furnace and water in your boiler. It’s one of the key components that provides heat throughout your home during cold winter temperatures.
When ignited, either by gas, propane or oil, the system channels hot combustion gases into the heat exchanger chamber to heat the metal walls. If your system is a warm air furnace, the return air ducts suck the cold air in your home into the furnace, which then passes over the heat exchanger to warm the air that gets distributed throughout your home. If you have a boiler, the return water passes through a coil that is heated by the heat exchanger to deliver hot water through your baseboard, thereby warming your home.
The heat exchanger system begins at the systems burner assembly and ends where it connects to the chimney vent. The heat exchanger is where flue gases from the burner assembly pass through to vent harmful gases to the outside of your home.
If you suspect your gas furnace has a cracked heat exchanger, you shouldn’t ignore the instinct. A damaged heat exchanger can be potentially hazardous to your family if not repaired immediately, as it exposes toxic gases like carbon monoxide.
There are telltale signs you have a problem with your heat exchanger. If the burner flame looks yellow, the burner can be dirty or damaged, or your heat exchanger can be cracked. Typically, the flame should be blue, providing insight that your system is functioning efficiently.
If you notice a lot of soot around your heating system or at the air vents of your ducted heating system, it may be a sign there is carbon spewing from your heating system. Soot is an indication that gases are not burning completely – this is known as incomplete combustion. Faulty or cracked burners, a cracked heat exchanger, or an issue with the flue vent, are a few reasons this can happen.
The most notable sign of a compromised or cracked heat exchanger is a strong smell. The fumes usually smell like formaldehyde and are highly toxic to your body when inhaled.