In a gas furnace, the heat exchanger is the component that is responsible for heating up the air inside the unit. Age and constant use of a gas furnace can lead to the heat exchanger cracking, which can lead to serious problems. If the heat exchanger has a crack, dangerous chemicals, such as carbon monoxide, that are created while the air is being heated can seep out. Thus, a cracked gas furnace heat exchanger is an issue that should be taken very seriously from a safety standpoint. Some common signs that your furnace may have a cracked heat exchanger that needs to be replaced by an HVAC professional include the following.

Soot Buildup

While soot may be common and not reason for concern in a wood burning fireplace, you should take action if you find suit building up in and around your home's furnace. Soot is typically caused by uncombusted carbon, so it's presence means that your furnace is no longer combusting and burning gas efficiently when producing hot air. While it is possible that soot buildup can be caused by burners that need to be adjusted, it is often a symptom of a cracked heat exchanger. When the heat exchanger is cracked, it changes the environment inside the heat exchanger, which leads to the inability to properly burn off the gas heating source.

Bad Smells

While carbon monoxide is usually odorless, the other gasses created inside the heat exchanger can smell really bad. If your furnace's heat exchanger has cracked, those gasses will seep out while the furnace is running, and you will likely be able to smell them. In addition to bad smells, the chemicals may cause eye irritation, headaches, nausea, and other symptoms. Any time you smell bad odors or suffer physical symptoms while your gas furnace is running, it is important to turn the furnace off and contact an HVAC contractor right away.

Obvious Signs of Wear and Tear

In many cases, a cracked heat exchanger in a gas furnace can be replaced and the furnace will then resume running properly. But, sometimes it may make more sense to replace the entire furnace. If your furnace is very old and has obvious signs of wear and tear or corrosion that is visible to the eye, there is a possibility that the heat exchanger may be cracked as well. Heating system inspections are important for all furnaces, but they are especially important for old furnaces that may begin to experience serious issues like cracked heat exchangers. 

For more information, reach out to companies like Lakeside Heating & A/C Inc.