If the heat exchanger rusts through or cracks, flue gases, including deadly carbon monoxide could leak into the home resulting in illness and possibly death of the occupants. Carbon monoxide poisoning can produce headaches, flu like symptoms, and even death.
A cracked heat exchanger poses a serious threat to the safety of your home. If there's a crack in one of the cells of the heat exchanger, the gases being burned – carbon monoxide, sulfur dioxide, nitrous oxide – could leak into your home, causing illness or, in extreme cases, death.
Heat exchangers can be very difficult to repair, and in many cases, a replacement is recommended. If your manufacturer's warranty has expired (or was voided due to lack of maintenance), the part and labor costs of a heat exchanger replacement will likely be far too expensive.
When your furnace kicks on, you may notice a dusty odor as the air first moves through the ducts and vents. Within a few minutes, the smell should disappear. If you notice strange smells, like formaldehyde or any other strong chemical smell, it strongly indicates that your heat exchanger is cracked.
So, can you run a furnace with a cracked heat exchanger? The straightforward answer is no. Operating a furnace under these conditions is unsafe and can lead to severe consequences, including the risk of carbon monoxide poisoning.
What is the cost to replace HVAC heat exchanger? It can range between $1,000-$4,000 for parts and labor, with an average cost of $2,000. Learn how this heat exchanger cost breaks down and how to identify the crucial signs it's cracked and needs replacement.
Even worse, a cracked heat exchanger can be a safety hazard. For instance, if natural gas is leaking from the heat exchanger, it can create a fire or explosion hazard. It can also potentially cause carbon monoxide leakage and build-up, which can be quite dangerous.
Your furnace might stop working if you're lucky, but most often, it will keep running even with a crack, allowing carbon monoxide to seep into your house. The only signs that you have a damaged heat exchanger are no heat during the winter, reoccurring flu-like symptoms, or a beeping carbon monoxide detector.
It is important that the heat exchanger is always in proper working condition. If it cracks or leaks, the exhaust gases, which include carbon monoxide, can mix with the air in your home resulting in a potentially deadly situation.
The metal surface of the heat exchanger is subjected to years of temperature extremes combined with expansion and contraction from multiple heating seasons. Another potential cause of cracking is limited air flow. Blocked registers, dirty filters, and ductwork obstructions can cause pressure to build up in the furnace.
Because replacing a heat exchanger can take up to eight hours or longer, it represents the bulk of the cost. If your warranty is expired, and you would need to pay both parts and labor for a new heat exchanger, look further into whether a full unit replacement would be more advantageous for you.
By using a combustion analyzer. This tool measures the efficiency of fuel burning appliances by determining the temperature and CO and oxygen levels. If the combustion analyzer detects low appliance efficiency, it means there's a combustion problem. A furnace combustion problem is a sign of a cracked heat exchanger.
Blower motor - $400 - $1,500. Heat exchanger - $500 - $1,500.
Soot can collect when combustion is incomplete. This can be caused by burners that are improperly adjusted or a cracked heat exchanger. A faulty heat exchanger will produce a strong and unpleasant odor that smells similar to formaldehyde.
Clogged filters reduce the air flow that result in development of cracks inside the system. Other reasons for reduced air flow are the dirty fan blades, dirty duct work, and obstructed air vents. All of these factors can cause major damage to the heat exchanger.
And remember, trying to replace a heat exchanger without professional assistance can pose potential hazards such as carbon monoxide poisoning and other safety risks.
Replacing Your Entire Furnace
Cracked heat exchangers typically occur in furnaces that are more than 15 years old, and the exchanger has been weakened over time due to corrosion. Even if the exchanger is replaced, an old furnace will soon need additional repairs or even full replacement.
The average cost of replacing your exchanger is about $1,500. However, it can cost as little as $500 or as much as $3,500. If the heat exchanger is cracked or malfunctioning before you would typically expect it, there may be another issue with your HVAC system.
However, carbon monoxide can travel throughout your home via your HVAC system, so it can still create a dangerous situation even when your furnace is off. You need to immediately leave your home and contact a skilled professional to deal with a furnace carbon monoxide leak.
Typically, you will need to switch out the damaged heat exchanger or replace the entire unit. The technician can give you a run-down of your options.
You should expect to spend between $3,800 and $12,00 on a new furnace, including both the unit and installation costs. Factors influencing the price include the type of furnace (gas, electric, or oil), the unit's efficiency rating, and the complexity of the installation.
A crack in the heat exchanger means combustion byproducts could escape and mix with the air supply that circulates throughout the home. Carbon monoxide is one byproduct of combustion, and exposure to this gas can be deadly. Another danger associated with a cracked heat exchanger is the possibility of a furnace fire.
Changes In How The Flame Looks
In a normal gas furnace, the flame will usually appear blue. A blue flame means that your furnace is working as it should. If this flame turns yellow, however, it might mean that your burner needs to be cleaned, or worse, that the heat exchanger is cracked.
The most hazardous of these gases is Carbon Monoxide. For this reason it is a must for you to have a carbon monoxide detector in your home. There is only one way to repair a cracked heat exchanger, and that involves either replacing the heat exchanger or the whole furnace itself.