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What is a “cracked” furnace? How serious is this?

On a routine trip to the attic, basement, or other location where your furnace is stored, you may notice that your furnace displays a scary-looking crack you hadn’t noticed before? Don’t panic. Although this is serious, it is also fixable. In lieu of noticing this issue visually, you may notice inefficiency in the way your heating system operates in your home which could be the result of a heat exchanger crack as well. Let us walk you through what to expect, what this means for your home heating, and how to get it repaired when the heat exchanger in your home gets a crack.

My Furnace is “Cracked” – What Happened?

There are many reasons your heat exchanger could crack. In addition to the usual wear and tear of an older furnace, here are a few reasons for metal erosion or seam cracks that we see most often:

  • Improperly-sized furnaces are more likely to crack due to excessive corrosion
  • Insufficient return-air going through the system causes metal stress
  • The 1-inch, pleated filters you’re using could restrict flow of air, which causes a metal seam to burst – this can also happen from infrequently changed filters
  • Water leaks from an unruly humidifier or AC coil can crack your exchanger
  • Poor manufacturing or manufacturer’s error can also cause cracks

What is the Risk of a “Cracked” Furnace?

The part that transfers heat from the gas flame to the air in the house is called a “heat exchanger”. If the heat exchanger has a crack or rust hole in it, the fumes (including carbon monoxide) enter the air that comes out of the supply registers into your home or office. This is why a “cracked” furnace can be so dangerous. A small crack may not be dangerous yet, it will get bigger and even small amounts of carbon monoxide can be dangerous. Heat exchangers can be replaced, however, if they are out of warranty, you are usually better off to install a new higher efficiency furnace.

Cracks in your heat exchanger can also cause your system to perform inefficiently resulting in less comfortable temperatures in your home as well as higher energy bills, due to energy misuse. Though these are less immediately dangerous outcomes, they can also be signs that your furnace needs to be looked at. If you ignore these signs, the risk of Carbon Monoxide poisoning could be imminent.

How Do I Fix My “Cracked” Furnace?

You don’t! We do. It is not safe for you to DIY the replacement or repair of your heat exchanger because you are unknowingly exposing yourself and your family to the harmful emissions from your system. Invite the experts from McCullough Heating & Air out to your home to inspect your furnace and repair your cracked heat exchanger instead. We see these issues all the time and we can help you safely and reliably fix this issue and prevent serious danger or damage from causing trouble for you. Contact us today at (512) 866-9821 .

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