If your furnace has started to make more or louder sounds than usual, you may end up needing to call in a technician for repairs. But before you do that, you should try to identify the new sound you're hearing and figure out if there's a way you can alleviate the problem yourself. Listen carefully to the sound to figure out where it's coming from. If the sound is coming from the motor itself, you'll probably need a technician, but if it's a problem with the ducts, there may be something you can do. Here are three ways you can solve furnace noise when it's localized in the ducts.
1. Rattling sounds
A rattling that occurs when the furnace is running and seems to come from the ducts is one of the easiest problems to fix. You'll have to listen closely to find out exactly which section of duct is at fault, but once you've done that all you have to do is tighten and/or pad the section. Check the screws, which may need tightening or (if they've wiggled all the way out) replacing. If that doesn't fix the problem, try securing the duct with duct tape and padding it with cork to absorb vibrations. If your furnace system is old, you may find several areas of duct that need this attention.
2. Whooshing sounds
A whooshing or whistling type of noise can indicate several different problems. The first and easiest to fix is an air filter problem. If the filter needs changing, the furnace will have difficulty getting air through it, meaning that it will have to try to get air from other places (such as through holes in the ducts). This abnormal passage of air causes a whistling or whooshing. Another way this sound can happen is if there's a hole in the duct work near the furnace itself. Air leaking through the hole can make a sound, so try plugging any holes to see if it helps.
3. Banging sounds
A bang that occurs inside the furnace itself when you start the furnace is bad news and requires an immediate visit by a technician. If you hear banging in the ducts, though, it could mean that you have a weak portion of duct that needs reinforcing. You'll have to use your listening skills again to find the area that's making the sound, and then you can reinforce it with a sheet of metal. This is a slightly more complex fix, so if you're not comfortable with it, don't be ashamed to call a technician.
Use these three methods to solve localized banging sounds that occur in your ducts. Remember, if you hear banging or other strange sounds inside the furnace itself, it's probably time to call for help. And if you're not positive what type of sound you're hearing or can't find where it's coming from, consider calling a technician such as Erickson Plumbing & Heating.