6 minutes read

Furnace Danger: Cracked Heat Exchanger

Stephen Jabro

Get the Facts on this Heater Carbon Monoxide Threat

Cracked Heat Exchanger in a furnace is a carbon monoxide threat

As a furnace gets older, there are many different kinds of problems it could have. While most furnace repairs are often relatively minor and don’t pose a big concern, a furnace with a cracked heat exchanger is a dangerous problem that must be addressed right away.

The reason why is simple. A crack in your heat exchanger could let gas escape from your heating system. That could cause carbon monoxide to seep into your home.

How Big is the Carbon Monoxide Risk?

While a cracked heat exchanger puts you at risk for carbon monoxide, it doesn’t always mean that CO is leaking into your home. It is possible that your heat exchanger could have a crack and is NOT leaking carbon monoxide.

This is obviously not a gamble you should make.

Because there is the potential that carbon monoxide could be leaking from a cracked heat exchanger, you should immediately take steps to get it safely handled by a professional HVAC technician.

Get emergency furnace repair in Springfield & Mt Vernon

Since a cracked heat exchanger poses such a potentially significant hazard, you should turn your furnace off and not turn it on again until the issue is completely fixed. Sometimes a professional who detects a crack will shut down your furnace in such a manner so that it cannot be turned back on to ensure the safety of everyone in the home.

Causes for Cracks in a Heat Exchanger

The leading cause for an exchanger to get a crack is from the unit overheating.

Cracked heat exchanger on a furnaceIf a furnace does not get sufficient airflow, the heat exchanger can get too hot and crack under the pressure of continually expanding and contracting.

So, if the issue is with airflow, it’s good to understand how airflow can get restricted.

It may sound odd, but simply having a dirty air filter is often why you do not have proper airflow from your home’s HVAC system. That is why having a clean furnace filter is the most important maintenance you need to do on your home’s heating system. This task is essential in preventing the likelihood of such dangerous problems as cracked heat exchangers.

Other issues, like a furnace that is too large or too small for your home, can also cause an exchanger to crack. A professional furnace installer will be able to identify exactly what size and type of furnace is right to safely and adequately heat your home.

Does this Problem Always Require a Repair?

Absolutely. A cracked heat exchanger is always a risk for dangerous, even deadly, carbon monoxide poisoning. The solution for fixing it is often to have your heat exchanger replaced. However, you may want to get your entire furnace replaced, especially if your furnace is more than ten years old.

How To Know if a Heat Exchanger is Cracked

Broken furnace in basement By taking a visual inspection of your furnace, you may be able to see a crack. But there are other signs, including:

  • Cracks or corrosion on other parts of the heating system
  • Soot build-up inside of the furnace
  • Wet floor near the furnace (not from condensation)

A cracked heat exchanger is not always easy to see. Often a crack cannot be detected by a simple visible inspection. Special tools and devices may need to be used to detect cracks that a homeowner cannot see on their own.

At Jon Wayne Heating & Air, we use a combustion analyzer to check for any cracks in your heating unit. A combustion analyzer provides oxygen and carbon monoxide readings to determine if there is any leak of any scale.

If you suspect you have a dangerous problem like a cracked heat exchanger, call Jon Wayne right away at (417) 831-9055 in the Springfield area or (417) 466-2515 in the Mt Vernon area. We will send one of our heating repair technicians out to accurately test your unit for cracks. We provide 24/7 emergency furnace repair service and can fix your system quickly and safely any time, any day.

Get emergency furnace repair in Springfield & Mt Vernon

Cost To Replace a Heat Exchanger

The typical cost for replacing an exchanger is between $600 and $1200. If your furnace is rather old, you may want to consider getting the entire furnace replaced. Our technicians are experienced in the repair and replacement of heat exchangers. We are also professional installers of new furnaces. We can provide you with the information you need to determine if a new heating system is your best option. You can request a free estimate online.

Cracked Heat Exchanger Repair Scams

There are stories of untrustworthy HVAC companies or handymen that claim a heat exchanger had a crack when that wasn’t the case. They may try to worry a homeowner about a CO leak to get work done that isn’t necessary.

If someone has told you that your heat exchanger is cracked, but you have reason to doubt their finding, contact Jon Wayne for a free second opinion. We pride ourselves on providing the most fair and excellent level of service and pricing. You can read testimonials from the many satisfied Missouri customers who recommend Jon Wayne Heating & Air.

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