9 Common Furnace Noises and What They Mean

After a few years of running your furnace every winter, you know how it’s supposed to sound. So it will likely catch your attention if the equipment starts making strange sounds. Some noises — like a few minor pops or clicks ahead of the warm air beginning to blow — are perfectly harmless. But others could affect the equipment or even jeopardize your health if you ignore them. Among the possible noises that you may hear, here are nine that justify an immediate furnace repair.

Scraping Furnace Noise

If you hear a sound like metal rubbing on metal, this could mean the blower wheel is becoming detached from the motor shaft, or the wheel or motor mount is broke. No matter the specific problem, you should shut off your furnace if you hear a scraping sound and call a professional for an critical repair.

Loud Boom at Startup

When you fire up your furnace, the burners should ignite without delay and start heating your home. A loud boom at startup potentially means the burners are dirty, resulting in delayed ignition. When the gas at last does ignite, you hear this terrifying furnace noise.

A small boom each time your furnace turns on could crack the heat exchanger, a costly repair that may force you to remove and replace the entire furnace. Act before it gets to this point! Turn 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 indicates poor lubrication. Multiple parts of a furnace need lightweight oil to function smoothly. If the parts are not lubricated, components grate against each other and cause unnecessary wear and tear. We suggest getting this problem remedied right away to prevent premature furnace failure.

Chirping Noise

The sound of a bird trapped in your furnace certainly warrants investigation. If you hear chirping coming from the furnace upon the first activation of the season, it could merely mean your furnace is warming up after months of no use. In this case, the sound should stop after a few cycles.

However, if the chirping does not end, it could indicate the pulley for the blower motor is out of alignment or the mounting plate is coming in contact with the blower wheel. This isn’t necessarily a safety hazard, but the only choice to get rid of the pesky furnace noise is to have a technician perform a repair.

Screeching Furnace

Screeching noises are an unmistakable warning sign that the fan belt is failing. If the fraying belt breaks, it could spin inside the furnace, harming other components and resulting in a much more expensive repair. Avoid this hassle and cost by replacing the worn-out belt sooner rather than later.

Persistent Clicking.

Some furnaces give off a fast series of clicks when they flip on and off. This is common and no reason to be concerned. That said, if the noise persists longer than about one minute, this could suggest an electrical complication. To avoid risking a house fire, call a furnace repair professional to fix the problem promptly.

Thwapping Sounds

The blower motor should perform smoothly when the furnace switches on. If you notice a thwapping sound that quickly picks up speed as the blower gets going, this likely means something is snagged in the fan, and the blades are smacking it with each rotation. A straightforward repair should be all you need to eliminate this pestering furnace noise and prevent 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 start there. If the rattling remains, the most likely culprit is a declining blower motor. Take this as a warning sign to have your furnace repaired before it breaks down completely.

Whistling or Vibrating

When your furnace has an air intake vent issue, you will often hear a whistling or humming vibration sound. If the whistling or vibrating comes from a vent, your ductwork is likely detached, 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 long term.

Schedule Furnace Repair with Service Experts Heating & Air Conditioning

Are you uncertain whether the furnace noises you hear align with these descriptions? It might be nothing, but if you want to be 100% sure, the easiest thing to do is to call a professional. At Service Experts Heating & Air Conditioning, we provide emergency furnace repair to get your heater performing properly as fast as possible. Be confident knowing that we stand behind our work with a one-year, 100% satisfaction guarantee. If you’re unhappy with our work anytime in the next 12 months, we’ll set things right! For more information or to arrange a furnace repair visit, please contact a Service Experts office near you.