November 2, 2019

It’s normal for a furnace to make a little noise as it revs up. Just be ready to investigate if your furnace makes banging sounds and they get louder or more frequent. You may have a broken part or ductwork problems that need to be addressed.

If you are tempted to call for furnace repair for a noisy banging or clanging sound, please do! A little maintenance can help the earache and make sure that your system is running efficiently and safely.

5 Reasons Your Furnace Is Banging

Furnaces make banging or knocking sounds when metal parts expand and contract, or when gas combustion occurs unevenly. Here are the 5 common underlying causes of banging furnace sounds:

  • Normal start-up noises: Metal parts expand and contract when a furnace cycles on and off. This is called knocking. You can usually ignore if it isn’t very loud, or there are no other signs of problems.
  • Loud pops at start-up: If knocking (or furnace banging) becomes louder than normal, you may have a dirty ignition system. The pilot or igniter is failing to ignite efficiently, then firing up with a bang.
  • Old or broken belt: A busted belt can cause the blower to make banging sounds. Belt problems will usually produce squeaky, whirring noises as well.
  • Duct noises: The banging sound may be coming from the walls of your ducts, not the furnace itself. The air filters may be dirty, or the ducts need to be sealed or repaired.
  • You need a new bypass damper: The device helps absorb vibrations that cause banging furnace noises. You might want to add a bypass damper or recalibrate or repair an existing one.
Do I Need Furnace Repair?

The bottom line is that some banging noises are normal at start-up and shut-down. If the banging gets louder, stranger, or starts to happen continuously whenever the furnace is on, then you should call for furnace repair.

We can provide a complete furnace tune-up to help reduce the banging noises. During the visit, the technician will investigate any necessary repairs. If we find a broken part, the repair will probably save you bigger headaches down the road. So don’t delay calling for furnace repair — unusual banging noises are reason enough to bring in the pros.

Baltimore Furnace Repair

Noisy furnaces aren’t just annoying — you may not be getting the efficiency and comfort due to a worn-out part. We offer scheduled and emergency service for furnace repairs in the Baltimore area.

Contact us immediately for great service from a team of heating experts!

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