If you've had your furnace for several winter seasons, you know how it’s supposed to sound. So you might be caught off guard if the unit starts making odd sounds. Some noises — like a couple of small pops or clicks prior to the warm air beginning to blow — are normal and harmless. But others could damage the equipment or even threaten your health if you dismiss them. While there are many more furnace noises to consider, here are nine that warrant an immediate furnace repair.
Scraping Furnace Noise
The moment you hear a sound like metal rubbing on metal, this could indicate the blower wheel has loosened from the motor shaft, or the wheel or motor mount is broke. No matter what the exact problem, you should shut off your furnace if you discover a scraping sound and call a professional for an emergency repair.
Loud Boom at Startup
When your furnace starts up, the burners should ignite immediately and get started heating your home. A loud boom at startup probably means the burners are dirty, which causes a delayed ignition. When the gas finally does ignite, you hear this terrifying furnace noise.
A small blast each time your furnace turns on could crack the heat exchanger, a costly repair that may force you to replace the entire furnace. Don’t let it come to this! Switch off your furnace if you hear a loud boom at startup, and avoid using it again until it has been repaired.
Squealing or Whining Sounds
A screaky or loud squealing furnace noise generally indicates poor lubrication. Like many mechanical equipment with moving parts inside, they need lightweight oil to function smoothly. Without this, components rub against each other and cause needless wear and tear. We suggest getting this situation remedied right away to avoid premature furnace failure.
The sound of a bird caught in your furnace definitely warrants investigation. If you notice chirping during the first furnace cycle of the season, it could just mean your furnace is warming up after several months of no use. In this situation, the sound should dissipate after a few cycles.
However, if the chirping doesn’t subside, it could mean the pulley for the blower motor is misaligned or the mounting plate is contacting the blower wheel. This isn’t automatically a safety hazard, but the only option to get rid of the irritating furnace noise is to have a technician perform a repair.
Screeching noises are an unmistakable warning sign that the fan belt is wearing out. If the fraying belt cracks, it could spin inside the furnace, harming other components and contributing to a much more expensive repair. Avoid this hassle and cost by changing the worn-out belt sooner rather than later.
Some furnaces give off a quick series of clicks when they switch on and off. There is nothing unusual about that. That said, if the noise persists longer than approximately 60 seconds, this could suggest an electrical complication. Don't risk an electrical fire! Simply call a furnace repair professional to solve the problem promptly.
The blower motor should operate properly 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 snagged in the fan, and the blades are hitting it with each rotation. A straightforward repair should be all you need to eliminate this annoying furnace noise and prevent damaging the blower motor.
A rattling furnace can be caused by multiple issues. It might be as easy as a loose door cover, so start there. If the rattling persists, the most plausible culprit is a malfunctioning blower motor. Take this as a warning sign to have your furnace repaired before it is an urgent situation.
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 separated somewhere, allowing conditioned air to release. These aren’t critical matters, but if you address it promptly, you’ll save money on your heating and cooling bills over the long haul.
Schedule Furnace Repair with Service Experts Heating & Air Conditioning
Are you unsure whether the furnace noises you hear match 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 have emergency furnace repair to get your system functioning properly as soon as possible. Feel safe knowing that we stand behind our work with a one-year, 100% satisfaction guarantee. If you’re dissatisfied 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 get in touch with a Service Experts office near you.