Is Your Furnace Making Odd Noises?

If your furnace (heater) is making loud or bizarre noises, it might be a warning sign of trouble. Furnaces are usually the one system in your home that can be ignored. However, you likely understand what sounds should be coming from your furnace when it’s running like it should, so noise that’s out of the ordinary needs your attention. Your furnace might get your attention by making some of these sounds.

  • Screeching Noise: If you hear a screeching noise, it may be a problem with the motor, or a bearing within the motor that is making the noise.
  • Metallic Chirping Noise: If you hear a metallic chirping noise, it could be caused by the wheel being out of alignment, a motor mount might be shaking loose, or your bearings could be failing. Occasionally you are sometimes able to wiggle the wheel to get the alignment to resolve itself, but if you aren’t certain of what you’re doing, it’s simply a better idea to have an accomplished HVAC tech check things out.
  • Rattling sound: If you hear a noisy rattling sound when your furnace shuts off, it is usually the metal parts to your furnace cooling down. However, it may also be something more unpleasant. The blower might be out of alignment or an error in the motor occurred. If you hear this noise you should give Precision a call.
  • Clanging noise: If you hear a clanging noise, the problem is typically in the pipes, rather than the furnace itself. This tends to happen when the pipes are able to cool down and contract after the furnace switches off.
  • Loud Boom or Thud: A loud boom or thud sound may start somewhere inside the ducts. They occasionally expand and contract in cold weather, especially if the furnace’s surroundings aren’t heated. However, it could also be an indication that the burners in the furnace are dirty and should be cleaned. These are pretty easy to clean on your own using hot soapy water. If you do attempt to clean these yourself, don’t forget to check that they are completely dry before putting them back. If you learn that it’s not the ducts or the burners, it may be that your gas valve is defective (if you have a gas furnace), which can result in a delayed ignition. In many cases, it is better to call Precision so one of our expert HVAC technicians can diagnose the problem.
  • Pinging and or Popping: A pinging or popping sound is typically coming from one of the ducts and is not generally something to fret over.
  • Odd Vibrating Noise or Whining: If you hear an odd vibrating noise or whining, it may be coming from a problem with your furnace. It might be serious, so a Precision technician really needs to check it out.
  • Loud Humming: A loud humming noise may come from when the furnace burners light and its cold outside. You can prevent this noise by turning the “off/pilot/on” control to reduce the burner flame.
  • Rattling Noise When the Furnace Starts Up: If you hear a rattling noise when the furnace activates, it might be a motor bearing going out.
  • Crackling Noise: A crackling noise is more than likely caused by the metal parts of your furnace cooling down when the furnace switches off.
  • Clunking and Banging: A clunking and banging sound indicates a cracked belt. If you hear this noise you should have a Precision HVAC tech out to your home to replace the belt.

Have Your Furnace System Examined by an HVAC Professional

If you want to be on the safe side, if your furnace is making sounds that are seem out of place its always a good idea to schedule one of our NATE Certified HVAC technicians to visit your home to do a system diagnosis to evaluate any possible problems before it’s too late. As they say, an ounce of prevention is worth a pound of cure.