9 Common Furnace Noises and What They Mean

Over time, when you fire up your furnace, you know how it’s supposed to sound. So you might be caught off guard if the system starts making unfamiliar noises. Some noises — like a couple of small pops or clicks prior to the warm air beginning to blow — are perfectly harmless. But others could impair the equipment or even threaten your health if you neglect them. Of all the furnace noises you might encounter, here are nine that are worthy of an immediate furnace repair.

Scraping Furnace Noise

When you hear a sound like metal against metal, this could indicate the blower wheel is becoming detached from the motor shaft, or the wheel or motor mount has broken. No matter what the exact problem, you should shut off your furnace if you hear a scraping sound and call a professional for an urgent repair.

Loud Boom at Startup

When you fire up your furnace, the burners should ignite immediately and get started heating your home. A loud boom at startup potentially means the burners are dirty, producing a delayed ignition. When the gas finally does ignite, you hear this frightening furnace noise.

A small blast each time your furnace turns on could crack the heat exchanger, a costly repair that might require you to remove and replace the entire furnace. Act before it gets to this point! Switch off your furnace if you hear a loud boom at startup, and don’t use it again until it has been repaired.

Squealing or Whining Sounds

A high-pitched squealing furnace noise usually signifies poor lubrication. Like many mechanical equipment with moving parts inside, they need lightweight oil to operate smoothly. Without this, components rub against each other and cause unnecessary wear and tear. Look into having this situation remedied right away to prevent premature furnace failure.

Chirping Noise

The sound of a bird trapped in your furnace absolutely warrants investigation. If you notice chirping coming from the furnace upon the first activation of the season, it could simply mean your furnace is warming up after an extended period of no use. In this situation, the sound should stop after a few cycles.

However, if the chirping doesn’t subside, it could indicate the pulley for the blower motor is out of alignment or the mounting plate is touching the blower wheel. This isn’t automatically a safety hazard, but the only choice to get rid of the pesky furnace noise is to have a technician conduct a repair.

Screeching Furnace

Screeching noises are clear and certain signs that the fan belt is failing. If the fraying belt cracks, it could spin inside the furnace, breaking other components and leading to a much more expensive repair. Avoid this hassle and cost by exchanging the worn-out belt sooner rather than later.

Continual Clicking.

Some furnaces give off a rapid series of clicks when they switch on and off. There is nothing unusual about that. Having said that, if the noise lasts longer than a minute or so, this could suggest an electrical complication. To avoid risking a house fire, call a furnace repair professional to fix the problem immediately.

Thwapping Sounds

The blower motor should perform smoothly when the furnace turns on. If you notice a thwapping sound that dramatically picks up speed as the blower gets going, this could mean something is caught in the fan, and the blades are striking it with each rotation. A quick repair should be all it takes to eliminate this annoying furnace noise and reduce the risk of damaging the blower motor.

Rattling Furnace

A few different problems can cause your furnace to rattle. It might be as basic as a loose door cover, so verify that option first. If the rattling remains, the most plausible culprit is a malfunctioning blower motor. Consider this a warning sign to have your furnace repaired before it entirely fails.

Whistling or Vibrating

Noises such as a teapot whistle or the hum of a vibrating item are signals of a problem with the air intake vent. If the whistling or vibrating comes from a vent, your ductwork is likely loose, allowing conditioned air to leak. These aren’t critical matters, but if you address it promptly, you’ll pay less on your heating and cooling bills in the long run.

Schedule Furnace Repair with Service Experts Heating & Air Conditioning

Are you unsure whether the furnace noises you hear correspond to these descriptions? Maybe nothing’s wrong, but the only way to know for sure is to call a professional. At Service Experts Heating & Air Conditioning, we provide emergency furnace repair to get your system functioning properly as soon as possible. Rest assured knowing that we stand behind our work with a one-year, 100% satisfaction guarantee. If you’re disappointed with our work anytime in the next 12 months, we’ll fix it! To find out more or to arrange a furnace repair visit, please get in touch with a Service Experts office near you.

chat now widget box