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Handling a Cracked Heat Exchanger


When it comes to furnace repair Waukesha WI, there are some repairs that definitely take priority over others. One of these is a cracked heat exchanger. This is not a minor repair by any means and isn’t something you should try to handle yourself.

If you think you have a cracked heat exchanger, you need to call an HVAC professional as soon as possible. This is a serious health and safety issue. Let’s take an in-depth look at the signs that your furnace has developed a cracked heat exchanger so you’ll know if this has happened in your home and what you should do about it.

Why Is a Cracked Heat Exchanger a Serious Issue?

The reason a crack in a heat exchanger poses serious problems is that it creates a major health hazard. To understand why you should know how a heat exchanger works. 

In gas furnaces, a heat exchanger is a metal container that collects hot combustion gas from the burners. The heat from the gas transfers to the metal walls, causing the exchanger to burn hot. Air from the blower moves around the exchanger and picks up the heat before it passes into the ventilation system. The remaining combustion exhaust in the exchanger is then sent through a flue to escape to the outside air.

If the heat exchanger has a crack, toxic combustion gases could potentially enter the air being blown into the rooms. This is a huge health hazard!

What Causes Heat Exchangers to Crack?

As they heat up and cool down, the heat exchanger’s metal chambers expand and contract. This strain can cause a crack to develop. Sometimes a reaction between the combustion gases and the metal occurs which leads to corrosion and weakening. 

How Do I Know If My Heat Exchangers Are Cracked?

You need to know the signs of a cracked heat exchanger because you won’t see them. These cracks are nearly invisible to the naked eye.

  • You can smell stinky odors such as rotten eggs, sulfur, or formaldehyde
  • Your carbon monoxide detector is going off
  • You’re suffering from headaches, nausea, dizziness, or flu-like symptoms
  • Your furnace isn’t heating properly
  • You hear a clicking noise from the furnace after the blower shuts off
  • Signs of corrosion anywhere on your furnace

What Should I Do If I Suspect My Heat Exchanger Is Cracked?

If anyone in your home is suffering from the physical effects of carbon monoxide poisoning, you’ll need to evacuate your home and call emergency services before doing anything else. The next step is knowing that this is a problem that can’t wait to be fixed and you should reach out to a professional HVAC company like ours for immediate repairs.

The Bottom Line

It’s important to keep up with maintenance to avoid this potential safety hazard. Although older furnaces are more likely to develop cracks in the heat exchanger, keeping up on maintenance every year can help avoid this problem or catch it early.

If you suspect you have a cracked heat exchanger, contact Capital Heating, Cooling & Electric. We’ve proudly served homes throughout Wisconsin since 2007.

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