March 31, 2021

5 Reasons Why Your Furnace is Rattling and How to Fix It

Furnaces are known for being a noisy part of your HVAC system. In fact, many noises are a part of normal operation, and evidence your furnace is working properly. But loud or unusual noises can sometimes be a sign something is wrong. One of the best ways to protect your furnace is to learn what noises your furnace should and shouldn’t be making.

A common noise many people hear is a metallic rattling. While sometimes it’s only because a bolt has shaken loose, other problems are more serious. In severe cases, rattling sounds could be evidence of a carbon monoxide leak. If you think something is wrong, don’t hesitate to call AC Mechanical at 307-778-0515 for furnace repair in Cheyenne.

Here are a few common problems that cause rattling sounds and how you can resolve them.


1. Cracked Heat Exchanger

The heat exchanger is one of the most important parts of your furnace. It catches and exhausts gases naturally created during the combustion process, including carbon monoxide. Because this part is subject to a lot of heat, it can crack as your furnace ages.

A cracked heat exchanger is very dangerous because it can leak carbon monoxide, a colorless, odorless gas that can you make extremely sick or even kill you in heavy concentrations.

When this part cracks, rattling noises are a very common side effect. You’ll typically hear the rattling sound before the blower turns on. If you hear rattling when your furnace is heating, the source may be elsewhere.

On average, heat exchanger replacement runs between $1,000–$2,000, according to HomeAdvisor, who compiles national averages for common household repairs. Your exact cost may vary depending on your specific furnace. If your furnace needs a new heat exchanger and is more than 15 years old, it may be best to do furnace installation instead.

Having furnace maintenance done each year helps spot problems like a cracked heat exchanger before it causes major problems. Maintenance also helps your furnace run more efficiently and may even help it last longer. It’s also important for keeping your manufacturer’s warranty valid, which may cover the cost of heat exchanger replacement during a certain time frame.


2. Ductwork

Rattling sounds after the blower has started often points to loose ductwork connections. Sometimes you can solve this problem on your own by sealing loose spots. But ductwork is often difficult to access, so a professional technician, like one from AC Mechanical, may be better suited to handle this job. Our expert staff can quickly find where the rattling sound is coming from and take the necessary steps to correct it.


3. Blower Wheel

Your furnace’s blower wheel is another important component because it helps the blower motor distribute warm air across your home. If the wheel becomes loose, it can rattle against the side of its housing. A rattling sound may also be a result of another piece of your furnace becoming lodged in the blower wheel.

Sometimes the rattling is a result of damage to the motor belt or blower wheel itself. These components are best repaired and replaced by a qualified professional, like one from AC Mechanical. We can get the job done quickly and safely!


4. Panel Covers

The outside of high-efficiency furnaces is covered by panels. A rattling sound here typically means something has shaken loose and needs to be tightened. A loose panel won’t typically affect how your furnace works, but it can create an annoying sound.


5. Bolts

As your furnace ages, its parts wear down. This includes bolts, which can make metallic rattling noises as they come loose. Most of the time these noises are unpleasant but won’t actually affect your furnace’s effectiveness. But if they’re shaken free, bolts can cause quite a bit of trouble.

Their small size may make them difficult to detect. If they become stuck elsewhere in your furnace’s machinery, important components may be damaged. While taking care of repairs, your AC Mechanical technician can check all bolts to make sure they’re secure.


Protect Your Furnace with AC Mechanical’s Help

Our technicians have the expertise to resolve a wide variety of furnace problems. If something is making an unpleasant rattling sound, our years of experience make finding the source of the problem fast and easy. The sooner we take care of the problem, the better chance your comfort won’t be interrupted.

If you’re hearing your furnace rattling or making strange sounds, give us call at 307-778-0515. We’ll resolve the problem quickly and affordably.

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