Why Is My Minneapolis Furnace Making Loud Noises?

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Now that your Minneapolis furnace has been running for a couple months now, you might notice some problems or noises that you didn’t notice before. Furnaces make a lot of noise naturally, but additional noises, like banging, scraping, or clanging noises, usually mean that something is wrong with your furnace. If you are concerned about noises your furnace is making, make sure to call your HVAC professionals right away. There could be something wrong with your furnace. Different noises usually come with different problems, so make sure you know what noise your furnace is making to see if there is something you can check before calling a technician.


Whistling noises from your furnace usually means that there is a problem with your air ducts. The first thing you’ll want to check is your air filter. If the filter is dirty, air will have a hard time getting through and create a whistling noise while getting by small areas between dirt and dust particles built up on the filter. If the filter is clean, check some of the air ducts for any small holes or cracks. Holes and cracks in your air ducts can be dangerous, and it decreases the efficiency of your furnace. Decreased efficiency means higher heating bills every month. If you can identify the place where there is a hole or crack in your air ducts, this will help get the process to fix it done faster.


Scrapes and Squeals

Scraping, like metal on metal, usually means that there is a serious issue with parts of your furnace that have come loose or broken. Other noises with the same result are rattling or vibration noises, but those will apply to loose screws or belts. With scraping noises, it most likely will be a loose blower wheel or motor.

Clangs and Thumps

Some noises can make your furnace sound like a washing machine. This could mean that your blower motor or wheel is out of balance, which is a serious problem for the furnace. Other kinds of clanging noises could mean that there is something stuck in the motor, there is a crack in the heat exchanger, or other serious issues with your furnace. In these cases, always call your HVAC professional to take a look at your furnace.


While some banging noises are normal when your furnace turns on, abnormally loud bangs are a cause for concern. Normal banging noises are caused by the air warming up and cooling down quickly, expanding or compressing the air ducts. Louder banging noises can mean a problem with the combustion. For a more technical term, this is called ignition roll out. It means that when the furnace turns on, there is a small explosion or the ignition flame is too big. This leads to serious problems with your furnace and should be looked at by an HVAC technician as soon as possible. There are other issues that cause loud noises, so be sure to check with your HVAC professional if there are noises coming from your furnace that aren’t normal.

If your furnace is making noises you aren’t sure about, call your HVAC professionals to schedule an appointment for a tune-up. Getting it fixed now can prevent many problems in the future.