HVAC Blower noise is a common complaint from homeowners and can be an annoying disturbance. There are different ways that help to quiet a noisy furnace blower. In many cases, a simple adjustment can correct the noise. In addition to fixing furnace blower noise, other causes could be preventing your system from running at peak efficiency and increasing energy consumption.
Are you looking for a quick answer on how to quiet your noisy furnace blower? The easiest solution is just to get a specially designed quiet HVAC blowe. The VIVOSUN 6 Inch 390 CFM Inline Duct Fan with Variable Speed Controller HVAC Blower and AC Infinity RAXIAL S6, Inline Booster Duct Fan 6″ with Speed Controller are the quietest furnace blowers in [year].
How Do I Make My Furnace Blower Quieter?
Check Air Flow
When airflow is restricted or blocked by debris, dust, or dirt, the blower has to work harder. Furnace air flow usually increases with temperature increase. Check the furnace filter and ductwork for any restriction that could be blocking proper airflow.
If your blower is running at high speed, it can cause the motor to generate audible noise.
A dirty Motor or blower Assembly can cause the motor to run hot and be noisy. If you have a heat pump system, check the supply and return registers for any restriction that could be causing your furnace blower to work harder than it should.
If there’s no restriction in the airflow path, verify the correct airflow for your furnace.
Building Sound Insulation
When your furnace is too loud, put some insulation around it to ensure you’re not waking up the neighbors.
The blower has a lot of ventilation channels on its outside surface, so adding more cloth or other soundproof materials.
Soundproofing furnaces will help absorb sound waves, reduce unwanted noise from reverberating inside homes, and use fans for circulation purposes, which are usually pretty loud when run at high speeds.
Correct Blower Speed
If the blower speed is too high, it can create a whistling noise and cause the motor to run hot. Verify the correct blower speed for your furnace; a typical problem with older furnaces is that they don’t have variable speeds and use only one speed, which is often set at high.
You can manually adjust the speed on most furnaces by turning a small knob or screw somewhere on the furnace. Verify correct blower speed with a thermometer and duct leakage test.
Blower Bearing Replacement
The blower bearing can be noisy and cause a howling noise. A bad blower bearing may not be repairable, and it should be replaced to correct the problem. If you are replacing your furnace blower bearing, consider upgrading to a long-life ball bearing instead of a standard style bearing.
Over time the blower wheel may become loose with wear and tear; this can increase noise from the blower assembly. If you have a single-speed blower assembly with only one belt, check to see if it is properly tensioned and replace it if needed.
Check Furnace Enclosure Noise Level
It may be possible to reduce the noise level by changing the furnace or blower enclosure. Blower enclosures made of metal can cause more noise than plastic, fiberglass, or other materials.
Blower Covers with Sound Attenuation Materials can reduce blower noise up to 10 dB(A). A quieter running motor will run at less power, reducing energy consumption.
Quiet Furnace Blower FAQ
What Is The Quietest Furnace On The Market?
The quietest furnace on the market is the AC Infinity RAXIAL S6, Inline Booster Duct Fan 6″ with Speed Controller.
Compared to other models, it is ENERGY STAR qualified.
It maintains an even heat distribution throughout your house and can be paired with any of AC Infinity’s compatible air conditioners for optimal heating efficiency.
Are 2-stage Furnaces Quieter?
Yes, in general, two-stage furnaces are much quieter than single-stage models when working at the lower settings.
The blower will also run less when in low-speed mode, which means it won’t make as much noise either. If you’re looking for a furnace that operates quietly, opt for a 2-stage unit.
What Causes Furnace Blower Rattling Noise?
There are many reasons why your furnace’s blower is making noise. It could be that the electric motor bearings need oiling, or there might just be loose sheet metal panels vibrating against one another.
Another possibility is that the blower wheel is out of balance. The shaking and rattling sound comes from the loose sheet metal panels vibrating against one another.
Why Is My Furnace Fan So Loud?
There are several reasons why your furnace seems excessively loud—here are a few common problems:
- Your house has inadequate insulation, which means that sound can easily escape.
- The furnace is unbalanced, so it vibrates and shakes more.
- Your furnace’s motor bearings are worn out or oiled too much.
- You have an airflow problem that causes the blower to malfunction, such as a dirty air filter.
- Your furnace’s bearings aren’t well lubricated, and the motor is vibrating.
- The belt that drives your furnace’s fan might be loose or not installed correctly, causing its vibrations.
- You have loose sheet metal panels rattling against one another.
Why Is My New Furnace So Loud?
If your new furnace seems excessively noisy, make sure to turn it off immediately and get an HVAC technician out for a service call before the warranty expires.
It’s also possible that your furnace’s blower wheel is out of balance, which can also cause the unit to shake and rattle.
The blower wheel can also have grease or oil on it, which would likely cause an oily smell.
When looking for a new furnace, try to find one with a low sound rating, so you know that it will be quieter than your old model. If all else fails, adding insulation to your house can help reduce noise. Read also: quietest mini split [year] and best anti-vibration pads for air conditioners
Final Words About How To Quiet A Noisy Furnace Blower
The noise reduction in a noisy furnace blower is mostly by changing the furnace or blower enclosure. Blower enclosures made of metal can cause more noise than plastic, fiberglass, or other materials.
Two-stage furnaces are quieter when working at the lower settings, and they run less in low-speed mode, which means they make less noise overall.
The VIVOSUN 6 Inch 390 CFM Inline Duct Fan with Variable Speed Controller HVAC Blower and AC Infinity RAXIAL S6, Inline Booster Duct Fan 6″ with Speed Controller are the quietest furnace blowers in [year].
Dave Pearson is a Canadian musician, sound editor, and audiophile. He is also the founder and owner of the website SoundProofGeek. On SoundProofGeek, Pearson offers advice and resources on audio equipment, including how to assess and improve audio quality, how to troubleshoot and repair audio equipment, and how to improve the music listening experience.