October 15, 2018
By Mark Paup

Scary Sounds Your Furnace Makes in the Dark!

Updated January 29, 2024

It’s October, so it seems appropriate to take the title of a much-loved children’s book of spooky stories and change it into our spooky blog post title. Because furnaces that make strange noises in the dark can be quite spooky! And most of the time, they’re telling people they need to be fixed. If your furnace makes you occasionally jump because of some weird clanging, rattling, or clicking noise, you don’t need to worry about specters or ghosts haunting your house—but you do need to worry about calling for furnace repair in Des Moines, IA. (Fortunately, you have us.)

Let’s take a closer look at some of these weird furnace noises that may interrupt your peaceful fall or winter, and what they may portend.

Clanging and Banging

Harsh metallic sounds like these usually indicate a moving part of the furnace have come loose. A likely candidate is parts of the blower fan, the fan responsible for moving air into the furnace to be heated and then into the ventilation system. Bent fan blades striking the blower fan housing are a strong possibility. For older furnaces, it could be a loose fan belt.


When a furnace starts up, you’ll usually hear a few clicking sounds like the electronic ignition (or standing pilot light for older furnaces) lights the gas burners. But you shouldn’t hear clicking noises at other times, especially after the blower fan shuts off. Clicking coming at these points often warns of a serious furnace issue: a cracked heat exchanger. Cracks in the heat exchanger can allow toxic exhaust fumes from the combustion process to enter the air blown into the house. Shut off the furnace and the gas and call for repairs to see if a cracked heat exchanger is the issue.


This is often a sign the furnace’s door is loose, or that bolts securing it to the ground are wearing down. If the problem persists after you secure the door or bolts, call for a technician to find out what might be causing it.


Is this sound scary, doesn’t it? But we’re talking about a mechanical shrieking noise—which is still not a pleasant thing to hear. And what it means is usually bearings in the motors are wearing down. If the bearings completely wear down, it will eventually cause the motor to fail. Calling repair people in time can save the motor by replacing the bearings.


This sound often indicates a motor is close to burning out. You may also notice an acrid smell coming from the vents along with the noise. Have repairs done as soon as possible—the motor will probably need to be replaced.

We must stress that you can’t do these repairs yourself! Gas furnaces must receive service from licensed professionals to keep them operating safely. Don’t take chances: call our team and we’ll handle fixing your furnace, fast and right.

If you want a Service Provider who will treat you and your home like their own, then call Golden Rule. “We Obey the Rules to Live By!”

Contact Us Today for HVAC Service!

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