Gas Furnace Heat Exchanger Failure - Dangerous Cracked Heat Exchangers in Furnaces

You can see the rust holes up near the sheet metal plates in this heat exchanger. This exchanger made the occupants sick.

Gas Furnace Heat Exchanger Failure - Richard, a technician just departed my house after looking at my gas furnace. My mom thought she smelled something so we called the furnace company we usually call when we need furnace maintenance to check it out.

He told us our heat exchanger in our furnace failed. I asked him how much it would cost to fix and he told me his service manager would call me with a price. I just got off the phone with the service manager and he said the furnace is still under warranty but we would have to pay for labor.

Gas Furnace Heat Exchanger Failure

The new heat exchanger is covered under the warranty. He said the labor cost would be $850.00 to replace the heat exchanger. The furnace is over 7 years old and the heat exchanger has failed? Isn’t this a major component of the furnace and if it failed in 7 years won’t the new replacement heat exchanger have this issue in another 7 years? What is supposed to be the lifespan of a furnace?

If so isn’t it a better decision to just replace the furnace altogether? And why would I want to buy this brand again if it failed so soon? We are cold right now but going to get some portable electric heaters. We need to make a decision soon. Thank you and I look forward to your answers. Jenna

Jenna, I am happy to help you. You’ve given me a lot of questions so let get on my soapbox and answer them and add a few things. Carbon monoxide is known as the silent killer. You can’t see it or smell it and it kills people every year.

It is always my recommendation that anyone with a fireplace, gas or oil furnace or any type of appliance that burns fossil fuels must have a carbon monoxide detector installed in your home. Your mother is not a good carbon monoxide detector although she did well in this circumstance.

Gas Furnace Heat Exchanger Failure | Exchanger Longevity

A gas furnace heat exchanger should last for the life of the gas furnace. Many manufacturers offer a lifetime warranty on heat exchangers or even 20 years on the heat exchanger warranty. The average life of any given furnace is 15 to 20 years and then it needs to be replaced.

There are a few reasons to replace a gas furnace before this time. First of all HVAC furnace manufacturers are constantly improving the efficiency of the gas furnaces. This is not only because of government regulations but also because gas gets more expensive over time. People can’t afford the old “gas hogs” of the past.

It’s a judgment call on your part for replacing the furnace or just replacing the heat exchanger. If you are planning on staying in the house for a long time I would replace the furnace. If you are only going to be there for a few years then I would replace the heat exchanger.

That would be how I would arrive at a decision and of course, it would depend on the budget. A new furnace will cost much more than just having the heat exchanger replaced.  As far as the brand is concerned check out our HVAC reviews website and pick out a good brand from our consumer furnace reviews.

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Gas Furnace Heat Exchanger Failure | Conclusion

When the heat exchanger is installed or you get the new furnace to make sure the HVAC technician properly checks all the gas furnace components. Additionally, that he ensures the pressures of the manifold are correct. I have seen some instances where the manifold pressure was way off. This can lead to a cracked or failed heat exchanger. It is important these technical issues are checked to prevent future problems with the gas furnace.

I’ve seen some installation technicians install a new system and turn it on. That’s it. No tests, nothing. As long as it provides heating and cooling they did their job. It is important to tweak settings to make sure everything is within range. All these little things make a big difference in operating costs and the longevity of the HVAC equipment.

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Gas Furnace Heat Exchanger Failure