Many households rely on a gas furnace for heating during the winter months. Depending on where you live, the winter season could be extremely taxing and require your gas furnace to work overtime to keep your home warm and comfortable. Older gas furnaces were less reliable and posed several dangers. Today, gas furnaces are highly efficient and safe pieces of equipment providing quality heating to many homes. Given that your gas furnace relies on complex processes and combustible materials, however, there are some safety considerations to be aware of. A cracked heat exchanger can be potentially hazardous.
A gas furnace’s heat exchanger transfers heat from combustion to air to warm your home. When ignited, hot combustion gases enter the exchanger, and the metal walls of the chamber are heated. As air is pulled in from your home, it is heated by the heat exchanger’s walls, and the warm air is sent through the ductwork into your house. The system also simultaneously blows out the combustion gases from the exchanger into a vent that funnels it outside. Under normal circumstances, this is a continuous process that safely heats your home to your desired temperature setting.
Throughout normal use, wear and tear can create small stress cracks in the heat exchanger. While some wear and tear, such as loose belts and small oil leaks, are harmless, a cracked heat exchanger could prove to be very dangerous. As combustion gas enters the exchanger, it could escape and mix with your home’s air supply. By-products of combustion include toxic carbon monoxide. Known as the silent killer, carbon monoxide has no smell, taste, or color, and exposure could result in serious health consequences or even death.
Due to the severity and risks, it is important that you know the cracked heat exchanger symptoms to watch for. Let’s take a look at some of the signs that you may have cracked the heat exchanger.
Visible Damage
You may be able to examine the heat exchanger and see the cracks. Cracks occur as the metal wears down due to the constant expansion and contraction during the heating process. You might also notice corrosion caused by moisture from the combustion by-products or chloride-containing fumes. A qualified HVAC technician will also be able to detect these cracks during your annual maintenance appointment.
Excessive Soot
When there is a lot of carbon in your system, the furnace will produce a lot of soot. In general, this happens if the furnace fails to burn the gas completely. There are several reasons for incomplete combustion, including faulty burners. However, a cracked heat exchanger is a common reason for more soot production inside your heating system.
Abnormal Flame
A typical furnace flame burns blue. If your heat exchanger is functioning correctly, you will notice a steady blue flame inside the unit. If the flame appears to be yellow, it could be a sign that you have a dirty burner or a cracked heat exchanger. If you notice a yellow flame that also flickers, you need to have your furnace examined by a professional HVAC technician as soon as possible.
Noticeable Odor
A cracked heat exchanger usually gives off a strong chemical-like smell. The fumes will usually smell like formaldehyde and are also very toxic if inhaled. If you notice a strong odor coming in and around your furnace, it is likely a heat exchanger issue. You will need to contact an HVAC contractor immediately and discontinue the use of the furnace until it is checked out. If you ignore this smell, you risk potential exposure to hazardous gases.
Cracked heat exchangers and carbon monoxide leaks are responsible for hundreds of fatalities in the U.S. each year. To keep your home and family safe, you need to have your furnace inspected and serviced annually. Additionally, you need to be keenly aware of any symptoms of potential danger.
