Squeak. Squeak. Squeak.
There are few things in this world that are more irritating than hearing a squeaking noise coming from your furnace fan.
In fact, they can be so annoying that some people opt to turn off their furnaces altogether just to escape the sound.
But in a world where winters are getting colder than ever, this could seriously end up putting your health at risk.
Instead, keep your home warm with our advice on identifying common squeaking noise issues and what you can do to fix these.
Blog Table of Contents
What is Causing This Squeaking Noise?
If your furnace is making a squealing sound, it could be due to a number of factors.
Furnace Blower Motor Bearings are Wearing Out
After your furnace produces hot air, it blows this back into your home through the use of a blower motor. This appliance works thanks to a blower motor wheel, which keeps the fan constantly moving.
Your furnace blower motor has several motor bearings which keep the blower wheel moving smoothly. However, with enough friction over time, these bearings will run down and eventually wear out.
Worn-out motor bearings will not be able to move smoothly, leading to an irritating squealing noise. So if your blower motor wheels are squealing, your first step should be to check your bearings to see if they’ve worn down.
However, we wouldn’t advise trying to fix these yourself because fixing blower motor bearings is a very technical process that requires a lot of experience.
Instead, look to contact an expert HVAC technician.
Furnace Blower Belt is Frayed
If you have an older furnace, you most likely have a belt-driven system. These systems use a belt attached to the furnace blower motor to keep the blower motor wheel moving.
A frayed blower belt or even a loose belt can produce a very irritating, high-pitched squealing or buzzing sound.
If you suspect your fan belt is frayed or loose, you can check your fan belt for visible signs of wear by removing the cover of your furnace blower compartment.
If there are no visible signs of damage, try pressing on the middle of the fan belt. If it moves more than 3/4th of an inch, then it definitely needs to be tightened.
You can do this yourself by unscrewing by the bolts of the furnace blower motor, adjusting the motor to make the fan belt firm, and tightening the bolts again.
If you’re not comfortable doing it yourself, consider contacting HVAC services. While these systems are not very common nowadays, an HVAC technician can still service them.
Alternatively, if these issues are becoming very frequent, you may want to consider getting a new furnace.
Dirty Air Filter
The air filter is one of the most important parts of your furnace. It keeps dust and dirt from getting into your home’s air by catching it before it’s blown out.
Otherwise, not only would your furnace be blowing warm air into your home, but also all the grime your system could be sucking in.
If your air filter is too dirty, the low airflow may create a high-pitched squeaking sound as too much air tries to force its way through the stuffed filter. Fortunately, this is a perfectly normal problem that’s easy to fix.
Simply turn off your system, remove the filter and replace it, and vacuum the inside of your indoor air handler clean.
You can avoid the low airflow problem by doing this every 3 months, if not more often.
Obstructed Vents or Ducts
If your air vents are obstructed by dirt or other substances, this can produce a similar effect to a dirty air filter: not enough air can pass through the ducts or vents, leading to a squealing noise as your furnace desperately tries to keep the airflow going.
If you notice extra loud ducts or vents, try making sure everything is open. Sometimes your problem might just be closed vents!
If you continue to notice the noise, this could be due to having something lodged in your system or even damaged ducts or vents.
In either case, you get a professional to look at your system because you risk damaging your system by trying to fix these problems yourself.
What if My Furnace is Making Other Noises?
You may be experiencing other kinds of noises coming from your furnace or HVAC system.
Fortunately, there are solutions available to address all sorts of weird noise coming from your central air system.
Furnace Keeps Making Clicking Noise
A clicking noise coming from your furnace can be caused by a few different things.
Your furnace could be suffering from a delayed gas ignition issue. This occurs when your furnace cannot keep a flame alight, leading to a “clicking” noise.
This could be due to a number of issues, such as a faulty ignition board or a bad valve. If you notice contracting air ducts, a malfunctioning pilot light, or not enough gas, contact a professional to look at your system.
A clicking sound can also come from the switches as the furnace starts another cycle. This shouldn’t be related to any issues in your system, but it could be causing this sound.
Rattling Noise Coming From Furnace
If you notice a rattling sound coming from your furnace, this is because your system is out of balance.
Your system needs to be kept in balance to function. To make sure of this, your blower motors have balancing weights that keep the system in alignment.
If these become unbalanced, this can cause a rattling noise. Alternatively, a loose part or scrap of sheet metal might be loose in your furnace, leading to a similar rattling or banging noise.
Whether it’s an issue of loose screws or an unbalanced furnace from a loose motor mount, you should get strange sounds like these checked by an HVAC system expert.
This is because these sounds may indicate greater problems with your blower motor, which could lead to long-term damage.
What Can You Do to Stop These Strange Noises?
The best way to avoid having any weird noise coming from your furnace and to keep it running efficiently and reliably is to get it regularly serviced.
Regular furnace maintenance can make sure your fan motor, blower fan, air ducts, and all the over important parts of your machine are functioning as they should.
This can save you money on energy bills by keeping your system as energy efficient as possible, as well as avoiding needing an expensive repair if one of these parts breaks down.
Final Thoughts on Strange Furnace Noises
Squeaky furnace fans can be caused a range of technical issues, from frayed parts to obstructed vents or a cracked heat exchanger.
If you start hearing these noises and are worried about your system, consider contacting Upstate Home Maintenance Services.
We’re experts on furnace repair and offer services all throughout the Spartanburg and Greenville counties. Get in touch with us via our contact page, and we’ll sort out the rest.
This article was written by Morgan Loch
Owner of Upstate Home Maintenance Services LLC and Local HVAC Guru
