Why is my furnace blowing so loud?

Author: Hilma Pfeffer  |  Last update: Thursday, November 20, 2025

If the sound is louder than typical and lasts longer than normal, it can be a sign of a problem with dirty burners, high gas pressure, or a malfunctioning heat exchanger, all of which could compromise the equipment's functionality and safety.

How do I make my furnace blower quieter?

How to Reduce Furnace noise? Please help
  • 1. Add a flexible connection in between the unit and the main trunk
  • 2. Add anti vibration pads under the unit
  • 3. Pull the unit another couple inches away from the wall
  • 4. Add sound dampening foam to the underside of the blower compartment
  • 5.
  • 6.

Why does my furnace sound like a lawn mower?

If your furnace produces a loud humming or buzzing sound, there could be an issue with the motor. There may also be something wrong with the fan. It can be something as simple as a loose screw, loose door, or improperly installed furnace filter.

Why does my furnace sound like a freight train?

7. Grinding, Scraping, or Clanking. If your furnace sounds like a train grinding and scraping away on tracks, then you probably have an issue with the blower wheel.

Why does my furnace sound like an airplane?

Blocked or undersized air ducts, closed vents, or a clogged air filter can force the furnace to work harder, leading to a loud noise similar to a jet engine. Solution: Inspect and clean or replace air filters and ensure all vents are open and unobstructed.

Noisy Furnace? - Top 5 Fixes | Repair and Replace

Why is my furnace so loud all of a sudden?

If your furnace suddenly produces loud, sudden banging or booms, you should call an experienced technician as soon as possible. These sounds could indicate stuck ignition, a potentially dangerous situation involving carbon monoxide which is deadly.

Should my furnace sound like a jet engine?

Yes, your gas furnace can sound like a jet plane when it's heating your home, but is that a bad thing? It could be a sign your heating system needs some serious maintenance. Furnaces can be loud, but if your furnace sounds like it's taking off from a runway, here are some helpful tips for your furnace troubleshooting.

Why does my furnace make a loud boom?

If you are hearing a boom sound coming from your furnace, the combustion chamber and burners can become clogged from grime and build up.

When should I worry about my furnace noise?

Loud Bangs, Rumbles, Knocks, or Booms

Loud noises like this are a sign of a build of gas in a furnace. The noise you hear can mean your heat exchanger is at risk of cracking. Even worse, it's a sign that something dangerous could happen if you continue to use your heater.

Why is my HVAC so loud when heat is on?

If your fan belt is wearing out, you may get a squealing noise while your HVAC system is running. Your motor may also need lubricant. HVAC motors require a very specific type of lubricant. If you are more comfortable with having an expert take care of it, an HVAC technician would be happy to help.

Why does my furnace sound like a leaf blower?

There are a variety of problems that can cause your furnace to produce loud noises. Types of noises such as scraping, banging, whistling, and popping may be a sign of a loose part, cracked heat exchanger, or dirty gas burners.

How much does a furnace blower motor cost?

While costs can vary, homeowners can typically expect the following range: Standard Blower Motors: These might cost between $400-700, excluding labor. Advanced Multi-Speed or Variable-Speed Motors: These are generally more expensive, with costs ranging between $650-1250, not including labor.

How do I lubricate my furnace blower bearings?

You'll probably have to remove an access plate to get at the ports. If the blower has grease cups instead of oil ports, remove the screw caps that cover the cups and fill the cups with bearing lubricant, which is available at automotive and hardware stores. When you lube the motor, you should also check the belts.

Why is my furnace intake so loud?

If the usual noise volume increases, or you start to hear flapping, rattling or high-pitched sounds from the supply vents, return grilles or ceiling diffusers, it's likely due to an increase in pressure caused by airflow restrictions somewhere in the HVAC system.

What brand of furnace is the quietest?

Top Quiet Furnace Brands
  • Trane. Trane is widely regarded as one of the top brands when it comes to quiet operation. ...
  • Carrier. Carrier is another leading furnace brand that prioritizes quiet operation. ...
  • Lennox. Lennox is known for its energy-efficient models, but it also excels in noise reduction. ...
  • Rheem. ...
  • Amana.

How to fix a noisy furnace blower?

Tighten the motor mounts and see if that solves your issue. If it doesn't, insulating the blower might be the best solution. If that doesn't work, then you may need to replace the whole blower. If the annoying sound is a screech, you might just need to oil the blower motor.

Why is my furnace louder than usual?

A loud buzzing noise almost always indicates that your furnace is working hard to generate warm air. This may mean that its blower fans are extremely dirty or that the motor powering the furnace fans is beginning to fail.

How loud should a furnace blower be?

A low hum is normal while the furnace runs, but if the noise is loud during a cycle or comes on when it wasn't present before, there could be an issue with the fan or capacitor.

How do I reduce the noise in my furnace?

Here are a few ways to reduce HVAC noise.
  1. Seal Air Leaks. Air leaks are one of the main causes of noise in HVAC systems. ...
  2. Upgrade Your HVAC System. ...
  3. Ventilation. ...
  4. Choosing the Right Location. ...
  5. Insulating the Walls. ...
  6. Cover Your Unit Using Soundproof Materials. ...
  7. Install Flexible Ducts. ...
  8. Get Duct Silencers.

Why did I hear a loud boom in my house?

Banging Noises from the Furnace Room

Simply reading the word “explosion” may cause a small panic, but it's actually a common problem that many homeowners experience. When the gas isn't ignited immediately, the gas starts to build up in the furnace until it finally reaches a flame and ignites. This causes a loud BOOM.

Why does my furnace sound like it's revving up and down?

Leaky or poorly connected ductwork can disrupt the airflow and prompt the furnace to work harder to compensate. This not only contributes to a revving sound but also compromises energy efficiency. Sealing and insulating ducts can enhance overall performance and reduce unnecessary strain on your furnace.

Why are high efficiency furnaces so loud?

All of these smaller parts contributed to your older furnace not being as efficient as your new one. For example, a smaller duct system could contribute to less air circulating through your home. This means that your new furnace is noisier because the larger size of its components allows you to receive more airflow.

What is the whoosh sound from my furnace?

You should only hear a gentle whoosh as the burners come on. If the sound is too loud, it probably means that ignition is getting delayed so that there is too much unburned gas in the combustion chamber that's igniting at one time. The ignition system may need to be replaced, or the burners might need to be cleaned.

Previous article
What is the best white paint to cover dark walls?
Next article
Does aluminum foil leach into food?