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No, That Cracked Heat Exchanger Cannot Wait

burnersThe official end of winter is almost here, though this last week could have fooled us! You’ve likely been using your heater on a frequent basis. Hopefully, you had maintenance done before the season began to help fend off any large Boise, ID furnace repair needs and improve heating operation—but these are just two factors to consider when it comes to furnace care. You also want to think about safety.

The only way to ensure the safety of your heater, and subsequently your home, is to stay on top of your furnace repair needs as much as possible. Maintenance will help with this, but it would also benefit you to be aware of common and not-so-common repair needs. One of the not-so-common but potentially hazardous furnace issues you might face is a cracked heat exchanger.

Is Your Furnace Gas Powered?

Then, you are at risk for a cracked heat exchanger. We don’t intend to cause panic with this statement—today’s heaters are built with safety in mind after all, and designed to be highly durable so long as they are professionally installed and cared for.

However, you must realize that any gas-powered appliance has the potential to be a safety hazard. Again, maintenance helps prevent this, but it’s still something important to be aware of.

More about Heat Exchangers

But wait…what is a heat exchanger? It’s the component within your gas-powered furnace that actually allows the system to heat up the air that travels through your ventilation system—your air ducts. When these burners come on, they generate hot combustion gas, which is collected inside the heat exchanger—a small metal chamber resembling a clamshell in shape.

This gas heats up the metal walls, and the blower fan of your furnace turns on, sending air around the exchanger. Heat is picked up from the furnace wall, and then continues into your ventilation system. This way, combustion gas can heat the air without ever coming into contact with your breathable air.

This process ends with the combustion byproducts in the heat exchanger being vented out of the system through a flue, where the gas is released into the outside air, harmlessly.

The Problem with a Cracked Heat Exchanger

The metal of your furnace’s heat exchanger expands and contracts with temperature fluctuations, and eventually the stress of this process can create cracks along the component. Another factor that can weaken the heat exchanger is corrosion from the reaction between the combustion gas and the metal (typically because of improper venting). The older your furnace is, the more prone to this problem it is.

These cracks are usually very small. In fact when your furnace is turned off the cracks might not even be noticeable to the naked eye. However, the heat exchanger expands with heat, therefore causing cracks to open up enough to allow combustion gas out and into your home’s airflow. This means harmful gasses are now infiltrating your home.

As concerning as this all sounds, we want to reiterate that maintenance will help you prevent any of this from occurring at all. Plus, it’s less likely to happen in a furnace younger than 10 years old. But a couple warning signs you should watch out for—or rather, listen for—are a clicking sound coming from the furnace soon after the blower shuts off, and of course your CO detectors going off. Do not use your furnace if either of these indicators present themselves, and do call for service right away.

For safe and reliable heating repairs, contact Ultimate Heating & Air, Inc today!

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