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Heater Exchanger Cracked? Here’s What To Do

How can I tell if my furnaces heat exchanger is cracked?

A cracked heater exchanger is a hazardous thing. There are certain signs that will tell you if it’s cracked, but here is all you need to know about heat exchangers and what to check if yours is cracked. Plus, what to do if you suspect you have a cracked heat exchanger on your furnace.


What is a Heater Exchanger?

A heat exchanger is a series of tubes inside (or a coil) inside your furnace that loops through the air through the furnace, causing it to heat and then be disbursed through the house.

This part of the furnace is integral to the actual heating of the air that goes through your house. It’s the spot in your furnace where the fire and gas connect and create heat. The combustion takes place inside the coils producing heat, which results in the heat getting blown out of the furnace and through the house.


Is a cracked heat exchanger bad?

Yes, when your heat exchanger cracks, it may not burn off all of the carbon monoxide and other gases in the furnace, causing them to leak into the house, which can cause illness and even death if not remedied quickly. The dangers of a cracked heat exchanger are gases not burning off properly and coming into the house, causing illness and discomfort and, in some cases, death.

A cracked heat exchanger is a severe thing and should be fixed immediately.


What causes heater exchanger cracks?

The most common reason for a cracked heat exchanger is that the airflow has been restricted. This can cause undue stress on the part of the heat exchanger causing the flow of air to slow down. This slowing is usually due to a dirty air filter and the build-up of dirt and other materials over time.

The clog means that the air does not flow through, so it cannot be heated. Without the air passing through to be heated, there is nothing to absorb the heat in the heat exchanger, and it gets hotter causing it to glow. The extra heat causes the metal to expand, and when it cools, the metal contracts. This can result in cracks in the heat exchanger if it continuously happens.

Another cause of heat exchanger cracks can be wear and tear in the valves that control the heat exchanger. A change in pressure in the

This can happen when a furnace hasn’t been properly maintained over the years. To prevent this, it’s a good idea to have an HVAC technician come out and periodically service your furnace to ensure it’s running in its best shape.


How Can You Tell If Your Heat Exchanger is Cracked?

It’s a good idea to be on the lookout for cracked heat exchanger symptoms. Here are the signs of a cracked heat exchanger.

The water around the floor of the furnace

If your furnace is leaking water, check for condensation first. If there is no condensation, it’s likely that there is a heat exchanger issue and needs to be inspected by a professional. That way, you can properly determine the source of the issue.


Odd smells

If your furnace starts to smell like a grade 10 biology class (read formaldehyde), it could be that the gas is leaking into the house and not being burned up. This gas can cause all types of issues, from nausea to headaches and much worse. If you are noticing a bad odor in the house or around the furnace, you may have a cracked heat exchanger.


Carbon build-up (aka soot)

As your furnaces gets older it can start to show its age; you may notice black soot building up, indicating that it’s no properly burning as cleanly and efficiently as it should. This can be an indication of a cracked heat exchanger.


Other cracks and damage on the furnace

Another one of the symptoms of the cracked heat exchanger is to inspect the furnace as a whole unit. If the furnace is older or has been used excessively over the years, wearing will naturally take place. This can break down on the internals of the furnace. It’s a natural part of the lifespan of a furnace that it will wear down over the years. Check to see if there are cracks and build-up in other places on the furnace. If you notice that there is significant aging, then you may have a cracked exchanger.


The health of your household

If there is a cracked heat exchanger, you and your family may be feeling ill without reason. When gasses are leaked into the house through the furnace, it can cause different symptoms such as flu or headaches. Other symptoms can be nausea, watery eyes, and runny nose, and these are all caused by leaking gases not being burned off in the heat exchanger.  These symptoms will be easy to detect since they are being caused by gases in the house. If you notice that you feel better when you leave the house or have been away for a weekend, it’s a good sign that there may be a leak in the house.


How to detect gases in your home

If the idea of noxious gases being in your home is disturbing, it’s a good idea to purchase a carbon monoxide detector. Place one in your furnace room and another in another part of the house.


Click here to buy a carbon monoxide detector. 


Can the heat exchanger be replaced?

Yes, it is possible to replace the heat exchanger unit on the furnace. However, depending on the age of your furnace, it may be better to replace the whole thing and upgrade to a high-efficiency furnace. A furnace lasts up to 20 years, and if you have had it for more than 15 years, it could be that other issues begin to pop up. If it is within your budget, replacing the whole furnace may be the right move to make.


Can you fix a cracked heat exchanger?

Once your heat exchanger has been cracked, it cannot be repaired; it must be replaced. Because the exchanger is located in the middle of the furnace, it will need to be disassembled for the new exchanger to be put in.


How much does it cost to replace a cracked heat exchanger?

Depending on where you live to replace a heat exchanger can cost you between $1000 to $2000. This is due to the part and nature of replacing the heat exchanger because it is in the middle of the furnace.


Should I replace the heat exchanger or buy a new furnace?

If you have a newer furnace, then it will make sense to replace the heat exchanger. This may mean that your furnace is still under warranty, and the cost of replacing it may be covered. But if you have an older furnace that is off warranty and is over 10 years old, you should consider replacing the furnace since the cost of installing a new furnace ranges from  $2,150 to $5,900. Buying a new furnace means they will take the old one out, dispose of it at a scrapyard near you and install the new one; plus, there will be a warranty on the new furnace, ensuring that it runs well for you over the next few years.


How long should a heat exchanger last?

A heat exchanger should last 10 to 20 years if properly maintained, but there are many other factors that can lead to the degrading and wear and tear of it that can make it crack sooner and stop working.


Final Thoughts on cracked heater exchanger on the furnace

If you have noticed any of the above issues, or you have suddenly lost heat in the house, it’s a good idea to call a professional HVAC technician and have them come out and see what’s the problem. They will have the tools to analyze the furnace and the gas combustion to see if a cracked heat exchanger is the problem.

If your heat exchanger is cracked, it needs to be dealt with immediately; shut your furnace off and contact a professional to come in and inspect your furnace.


Click Here to Find a Repair person.


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