Is Your Furnace Making a Loud Humming Noise? Here are 5 Possible Reasons

January 9, 2022

It is perfectly normal for the furnace in your home to make noise throughout the day. In fact, it's easy to forget how loud our home is until a power outage strikes, leaving most household appliances in non-functioning condition. 


Though, if your furnace starts to make a strange humming noise, there is a good chance that you're in need of a timely furnace repair. A loudly humming and buzzing furnace typically indicates there may be an issue that requires immediate, professional attention.

That's why the furnace installation, repair, and replacement
experts at Excelsior Mechanical have made the following list; five reasons your home's furnace is making a loud humming noise. Read on to learn more. 


The Blower Motor Does Not Have Enough Lubricant


One of the most common reasons for a loudly humming furnace is a lack of lubrication for your blower motor. A blower motor that isn't properly lubricated can become the source of annoyingly loud, buzzing noises that could indicate an impending motor failure. 


If you suspect that your blower motor isn't properly lubricated, try lubricating it yourself, restarting it, and then listen for a persistent hum.

However, if you’d rather have an expert look; furnace repair and replacement specialists like those at Excelsior Mechanical, offer fast and easy motor lubricating as part of a range of
heating repair services for homeowners living in or around the Saskatoon area.


Failing Transformer


A noisy furnace can also be an indication that the transformer is failing.


It is normal for your furnace's transformer to make some noise, but a constant humming noise that's noticeably loud may indicate that your transformer is in need of repair. We recommend that you contact a team of heating repair and replacement professionals, like those at Excelsior Mechanical, to inspect your transformer for irregularities that you may not otherwise notice yourself.


Loose Equipment


It is not uncommon for older, poorly maintained furnaces to have loose equipment that contributes to a loud, noisy hum or rattle.

Loose equipment like nuts and bolts, as well as the belts inside your furnace, can not only contribute to annoying sounds but can also lead to the eventual failure of your entire furnace system. Loose equipment in your furnace is best dealt with by trained professionals that can quickly diagnose and address pieces of equipment that need to be re-fastened or otherwise replaced.


Loose Ductwork


In addition to the furnace belt, nuts, and bolts that all can come loose within your furnace system, the ductwork in your furnace can also come loose if your ventilation system's joints and seams suffer from too much wear and tear.

It is important that you quickly secure and seal the ductwork in your furnace to avoid a constant humming noise and the eventual failure of your furnace.


Broken Capacitor 


Last but certainly not least among the most common reasons for a loudly humming furnace; a capacitor that is broken. A failed capacitor is easy to spot if you notice that your furnace is on and audible however the motor isn’t spinning. Once you're certain that your furnace's motor isn’t turning, it's imperative that you call furnace installation, replacement, and repair specialists, like those at Excelsior Mechanical, to have the parts you need quickly repaired or replaced.

Contact Us

We offer assistance and service for all aforementioned issues and much, much more for homeowners in the Saskatoon area.

Do you need immediate assistance with your home furnace? Don't wait around for the expertise you're looking for; call us today at 306-652-1795 or
get a free quote by visiting our Contact Us page!


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