Why Is a Cracked Heater Exchanger Such a Problem?


Gas furnaces are one of the most popular ways to heat a home. With any combustion system, it is very important to make sure that the components are checked annually for both operational and safety reasons. One of the components that must be checked to ensure continued safety in your home is the heat exchanger. This large, metal component can corrode and crack, and cracks in a heat exchanger are very serious. We’ll outline some reasons why a heat exchanger can crack, but should you ever suspect you have a heat exchanger issue, contact your Ideal Services heating repair technician right away.

What Is a Heat Exchanger?

A heat exchanger is a metal component inside the firebox of your furnace. It usually consists of medium-sized metal tubes that are heated up when the burners ignite. The inside of the tubes are hollow so they can collect and exhaust the toxic flue gases that develop during the heating process; if there are cracks in your heat exchanger, these toxic fumes will escape into your home.

Reasons Heat Exchangers Crack

  • Excess moisture – your furnace creates moisture when it cycles, and this moisture is removed via a condensate drain. Should the drain clog or malfunction in any way, the moisture may not drain properly, and instead accumulate on the heat exchanger. The difference in temperatures between the moisture and the combustion can cause the metal to crack.
  • Age – age is one of the most common reasons for a heat exchanger to crack. The metal of a heat exchanger is constantly expanding and contracting with normal operation; at some point, this wear and tear can result in the metal cracking.
  • Decreased air flow – when there is too little air flow in your system, the heat exchanger can become too hot. Too much heat can weaken the metal, which enables cracking.

Problems Caused By a Cracked Heat Exchanger

Here are some problems that can develop from a cracked heat exchanger:

  • Carbon monoxide poisoning – as we mentioned above, when a heat exchanger cracks, the toxic fumes from inside the tubes escapes into your home; this includes carbon monoxide. This can be a very dangerous situation and is only remedied by replacing the heat exchanger.
  • Poor combustion – a heat exchanger can’t work as it should with cracks in the metal; as such, the air-to-fuel ratio is affected, and will affect the combustion in your system.
  • Significant soot buildup – soot is removed with the toxic flue gases; with cracks in the heat exchanger, soot will escape and coat the various parts of your system, further decreasing your system’s ability to perform.

There is no repairing a cracked heat exchanger; it must be replaced, and it should always be replaced by a trained and certified professional. For over 20 years, Ideal Services Heating & Cooling has helped customers with quality heating repair service, so if you are experiencing problems, give us a call today (919) 887-9680 .

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