Why Is My Furnace So Noisy?
John Turpin is our resident home service repair expert here at Service Direct. He’s got the knowledge and experience to help homeowners like you make sense of most home repair issues. And with Service Direct, we connect you with top-tier service professionals to help with any repairs needed.
Find Out Why Your Furnace Has Been Making So Much Noise
The furnace should help keep you warm, but it’s not doing that right now. Instead, you’re kept awake at night wondering, “Why is my furnace noisy?” You hear banging and clanging whenever it’s on, sometimes so loud you have to turn up the TV volume to drown out the sounds.
It’s tempting to just ignore it, but we don’t recommend that. A noisy furnace could mean an underlying problem, which can lead to a more serious issue. It’s best to check it and address the issue as soon as possible.
With that said, we’re here to explore the possible reasons why your furnace has been making so much noise. By understanding the common causes of furnace noises, you’ll know what to do to resolve them and ensure your heating system continues to make your home comfortable.
Common Reasons Why Your Furnace Is Noisy
Loose or Damaged Components
One of the most common culprits of a noisy furnace is loose or damaged components. Over time, regular use and vibrations can cause screws, bolts, or other parts to become loose. As a result, you may hear rattling, banging, or clanking sounds.
Also, components such as motor mounts or blower wheels can become worn or damaged, leading to strange noises. If you suspect loose or damaged components, we advise reaching out to a professional HVAC technician.
Dirty Furnace Burners
If you hear a loud boom or a rumbling noise when the furnace starts up, it could be due to dirty furnace burners. Dust, debris, and rust can accumulate on the burners over time, disrupting the combustion process and causing noise.
Regular furnace maintenance, such as cleaning the burners, should help fix this issue. However, it’s best to leave this task to a trained technician to ensure safety and proper cleaning techniques.
Clogged Air Filters
“Why is my house heater so loud?” Maybe it’s because the furnace’s air filters are clogged. Air filters play a crucial role in maintaining the furnace’s efficiency. When they become clogged with dirt, dust, and debris, they restrict airflow and put additional strain on the system.
This can result in whistling, whining, or vibrating noises. Regularly cleaning or changing your air filters can prevent this problem. It’s recommended to check the filters at least once a month and replace them as needed.
Faulty Blower Motor
The blower motor is the part of the furnace that circulates the warm air throughout your home. If it starts making squealing, grinding, or humming noises, it could be faulty. Over time, the motor bearings may wear out, causing friction and unusual sounds. Ignoring this issue can lead to complete motor failure. You should contact a professional HVAC technician promptly to diagnose and repair or replace the faulty motor blower.
Ductwork Issues
Noises originating from the ductwork can sometimes be mistaken for furnace noises. Loose or disconnected ducts can create banging, rattling, or whistling sounds as air flows through them. Inspecting your ductwork for any visible damage or loose connections is a good starting point for resolving this issue. Get in touch with a qualified technician to perform a thorough inspection and fix any ductwork issues to restore your furnace’s quiet operation.
Our resident home repair guru, John Turpin, explores the different potential reasons for your furnace making a lot of noise, as well as some useful DIY troubleshooting suggestions.
Normal Operational Sounds
Why is your furnace noisy? Well, are you sure it’s noisy or are you hearing normal operational sounds? While some furnace noises indicate underlying problems, it’s important to note that not all sounds are cause for concern. Some sounds, like the sound of the blower turning on and off, are normal. But if you notice any sudden or excessively loud noises that you haven’t heard before, it’s worth investigating further.
Belt or Blower Assembly Issues
Older furnaces may have a blower assembly with a belt that connects the motor to the blower wheel. The belt can wear out over time, or become misaligned, resulting in screeching or squealing noises.
The blower itself may also accumulate dirt or debris, causing it to become unbalanced and produce a loud vibrating or humming sound. Regular maintenance, such as lubricating the blower assembly or replacing the belt, can help prevent these issues.
Expansion or Contraction Noises
As your furnace heats up and cools down during its normal operation, the metal components expand and contract. This can lead to popping, cracking, or ticking noises. While these sounds are usually harmless and common, they can become more noticeable in older furnaces or if the ductwork is close to the living areas. If the noises become more frequent or excessively loud, we advise having an HVAC technician inspect the furnace to ensure everything is functioning properly.
Improperly Sized Ductwork
Sometimes, noisy furnaces can be attributed to improperly sized or designed ductwork. If the ducts are too small for the furnace’s airflow requirements, it can lead to increased pressure and airflow restriction.
As a result, you hear whistling or vibrating noises coming from the furnace. On the other hand, oversized ducts can cause excessive air movement that results in loud rushing or whooshing sounds. Consulting with an HVAC technician can help determine if your ductwork needs to be resized or modified to optimize your system’s performance, and reduce noise as well.
Ignition or Gas Valve Problems
Do you hear a clicking sound followed by a delay in the ignition of your furnace? This could mean an issue with the ignition or gas valve. The clicking noise usually indicates that the ignition system is trying to ignite the burners.
But if there’s a delay or the ignition fails, it can lead to a gas buildup and an explosion when the gas actually ignites. It can be dangerous and requires immediate attention from a professional technician. As such, don’t delay reaching out to a pro to address the ignition or gas valve problem.
Is it normal for a furnace to make some operational noise?
Yes, some operational noises, like a gentle hum or the sound of the blower turning on and off, are normal for a furnace. But any sudden or excessively loud noises that are out of the ordinary should be investigated further.
Can I fix a noisy furnace myself?
There are some basic maintenance tasks you can perform on your own, such as replacing air filters. But in most cases, it’s recommended to have a professional HVAC technician handle repairs for a noisy furnace. They have the expertise, experience, and tools to diagnose the root cause of the noises accurately and ensure it’s properly fixed.
How can I prevent my furnace from becoming noisy?
Regular maintenance is crucial for preventing furnace noise. This includes changing or cleaning air filters regularly, scheduling professional inspections and cleanings, as well as addressing any issues promptly to avoid further damage.
Can the size of the furnace affect its noise level?
Yes, the size of the furnace can impact its noise level. An oversized furnace can produce excessive airflow and noise while an undersized furnace may strain to meet heating demands, leading to unusual noises. Consulting with an HVAC professional can help ensure your furnace is properly sized for your home.
Hire a Local HVAC Pro
A noisy furnace can be disruptive and alarming, but often it’s a sign of something that needs attention. When wondering, “Why is my furnace noisy?” it could be loose or damaged components, clogged air filters, dirty burners, or just normal operational sounds. Whatever it is, our qualified HVAC professionals are just a form or phone call away.