After a few years of running your furnace every winter, you know how it’s supposed to sound. So you'll likely notice if the system starts making unfamiliar noises. Some noises — like several small pops or clicks before the warm air beginning to blow — are perfectly harmless. But others could ruin 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
If you hear a sound like metal scraping on metal, this could suggest the blower wheel is becoming detached from the motor shaft, or the wheel or motor mount is damaged or failing. Regardless of the specific problem, you should turn off your furnace if you notice a scraping sound and call a professional for an critical repair.
Loud Boom at Startup
When you start your furnace, the burners should ignite right away and get started heating your home. A loud boom at startup potentially means the burners are dirty, producing a delayed ignition. When the gas eventually does ignite, you hear this scary furnace noise.
A small explosion each time your furnace turns on could break the heat exchanger, an expensive repair that might require 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 avoid using it again until it has been repaired.
Squealing or Whining Sounds
A high-pitched squealing furnace noise generally signifies poor lubrication. Multiple parts of a furnace need lightweight oil to run smoothly. If these parts are dry, components grind against each other and cause unwanted wear and tear. Our recommendation is to have this situation remedied right away to prevent premature furnace failure.
Chirping Noise
The sound of a bird entrapped in your furnace certainly warrants investigation. If you hear chirping coming from the furnace upon the first activation of the season, it could simply mean your furnace is warming up after months of no use. In this case, the sound should end after a few cycles.
However, if the chirping does not end, it could indicate the pulley for the blower motor is crooked or the mounting plate is contacting the blower wheel. This isn’t always a safety risk, but the only option to eliminate the irritating 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, breaking other components and leading to a much more expensive repair. Avoid this hassle and cost by changing the worn-out belt sooner rather than later.
Repeated Clicking.
Some furnaces give off a quick series of clicks when they switch on and off. This is completely normal. That said, if the noise lasts longer than a minute or so, this could suggest an electrical issue. To avoid risking a house fire, call a furnace repair professional to fix the problem promptly.
Thwapping Sounds
The blower motor should operate without problems when the furnace activates. If you discover a thwapping sound that dramatically picks up speed as the blower gets going, this likely means something is snagged in the fan, and the blades are hitting it with each rotation. A straightforward repair should be all it takes to eliminate this annoying furnace noise and protect against damaging the blower motor.
Rattling Furnace
A rattling furnace can be caused by multiple issues. It might be as simple as a loose door cover, so check this first. If the rattling remains, the most plausible root cause is a declining 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 loose, allowing conditioned air to escape. These aren’t urgent matters, but if you have them fixed quickly, you’ll spend less on your heating and cooling bills long term.
Schedule Furnace Repair with Service Experts Heating & Air Conditioning
Are you unsure whether the furnace noises you hear align with 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 unit functioning properly as quickly as possible. Rest assured 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 fix it! For additional information or to arrange a furnace repair visit, please speak a Service Experts office near you.