What Causes a Furnace to Vibrate When It Turns On?

Unusual furnace sounds spark fear among Montgomery homeowners, as many worry it’s the sound of expensive repair needs, or even the furnace’s last words, so to speak. Luckily, not all furnace noises spell major heating system issues. For example, if a furnace vibrates when starting, the possibilities include a loose panel or a disconnected duct. In our most recent blog, the technicians at Hans Heating & Air discuss what causes a vibrating sound as your furnace starts up and what you can do to end this noisy problem.

1. Loose Panel

The internal components of a furnace are protected by a metal cabinet, which has access panels that can be removed to access the heating system’s inner workings for repair. If your furnace is vibrating when starting, the simplest explanation is a possible loose panel.

The access panels should fit flush and snug but might be loose due to:

  • Someone accidentally leaving the panel loose after servicing or inspecting the furnace.
  • The screws holding the panel in place are worn, which causes a loose fit.

To fix this problem, use a screwdriver to tighten up loose screws that hold the panel in place. If the furnace is still vibrating when starting again after you address the loose screws, call your HVAC company for service to find the source of this problem.

2. Loose Blower Motor or Blower Fan

The furnace’s blower motor and blower fan rotate to push heated air through the duct work and into your home. Over time and thousands of revolutions, these components can work their way loose. When the furnace vibrates when starting, it’s the sound of those components going to work, and the loud noise will probably continue for the full heating cycle. These components need to be reattached to their mounts by a professional to eliminate the vibration.

3. Item Inside Blower

While the furnace’s access panels keep most unwelcome things out of the system, it is possible for a breach to occur. Dirt, debris, or even pests can enter the blower assembly through an open or removed panel. The furnace might vibrate when starting because the blower components strike or rub up against this object as they start to run. Turn your furnace off, remove the access panel and take a peek inside the blower compartment – if you see debris or other items, remove them. If the source of the vibrating sounds cannot be identified, call for service.

4. Disconnected Duct

Duct work is made of sheet metal, and pieces are secured by metal brackets. Constantly subjected to moving air, their connections may loosen or disconnect entirely. Once a heating cycle begins and air resumes circulation through the ducts, you may notice a vibration when the furnace starts – this is the noise produced as the metal components vibrate against each other.

Disconnected ducts aren’t typical but can result from poor installation. Have your duct work professionally inspected and repaired if necessary.

Contact Hans to Stop Troubling Furnace Noises

Whether your furnace vibrates when starting or makes another unusual sound that has you concerned, Hans Heating & Air is the trusted Montgomery heating company that will put an end to the bothersome racket. Schedule furnace repair today, and enjoy quiet comfort again shortly.

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