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Why is My Furnace Making a Rattling Noise?

Published by Luke Weiden

Winters in Chicago are, for the most part, quite cold given the lakefront effect. Having a working furnace comes in handy to keep you warm, but, when the furnace breaks, the cold weather can make your home uncomfortable and hazardous. Therefore, it’s important to be aware of any signs of breakage in your furnace. 

Pay attention to any loud rattling or grinding noise coming from the furnace. If you hear loud noises, keep reading to learn what it means and what you should do.

The Main Causes of Furnace Rattling

Furnaces have a lot of parts. If you hear any rattling sounds or clicking noises, it may be due to

  • A loose panel or screw in the heat exchanger: These parts commonly break off over time. Moreover, there’s a greater risk if your air ducts and burners are dirty. Too much debris can cause internal disruptions and lead to excessive noise.
  • Broken motor fan: Typically, furnace blower fan rattling noises stem from a fan belt issue. This is due to the motor fan breaking off from the motor bearings. As a result, you’ll hear the blower wheel grind against the bearings which can be loud and unsettling.
  • Exhaust vents blockage: Trapped air can cause noise in your furnace if you have blocked exhaust pipes trapping the air inside.
  • Dirty burners and pilots: If your pilot light gets clogged, the furnace may make deep rumbling sounds as it tries in vain to start heating.  

A repair technician inspecting a central gas furnace.

What to Do if You Hear Furnace Noises

Fortunately, a noisy furnace is not the end of the world. However, if your furnace makes rattling or grinding noises, call a professional repair technician for maintenance. They will thoroughly inspect the unit checking for issues and causes of the problem. Afterwards, they will make the appropriate repairs to fix it.

Most of the time, a repair technician will replace broken parts with new ones. But in some cases, replacing the furnace might make more sense. If your furnace is already nearing the end of its life, paying for expensive repairs may end up being a waste of money. If a different part gives out the following year, you’ll be back at square one. So with older units, it often won’t make sense to pay for repairs when you could’ve put that money toward a new unit.

Mainly, if your furnace is older, amounts to high energy bills, and is not performing efficiently, replacing it generally makes more sense than keeping it around.

How Deljo Can Help

At Deljo, we’ll explain the issue and your options for moving forward. We’ll always provide our honest, professional opinion as to the best solution for your specific needs and budget. And with the knowledge and experience to pinpoint any problems with your furnace, we ensure excellent, affordable solutions to keep you warm all year long.

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