Why Does My Furnace Make Weird Noises?

furnace

Is your furnace making strange sounds? Do you have a sneaking suspicion that something’s wrong or seems to be “off” with your HVAC equipment? In general, it’s wise to trust your senses and call an HVAC technician at the first bump in the night that comes from your heater.

What are the most commonly reported weird furnace noises, and what do they indicate? See if yours is on our list below. Sometimes, you can troubleshoot issues without the help of a technician. Other times, you may want to contact a service provider right away.

Why Do Furnaces Make Loud Bangs or Other Noises When Kicking On?

Hearing a loud “bang” when your furnace starts up can be disconcerting. Is the furnace about to explode? Probably not. Still, this is one type of noise you don’t want to ignore.

Many times, dirty burners are the culprit for banging. On the other hand, if the sound isn’t super loud, the banging could just be your ducts adjusting to the sudden rush of air. Still, it’s best to get a professional’s opinion to determine the root cause of the banging and whether or not your furnace requires a bit of maintenance.

Why Does a Loud Buzzing Noise Come From Our Furnace?

Humming and buzzing could point to a faulty transformer that’s on its last legs. Don’t put off having someone diagnose buzzing, though. You certainly wouldn’t want the transformer to stop working on the coldest night of the year.

Why Is a Whistling Sound Coming From the Furnace?

Do you hear a whistle from your furnace? Whistling could be air leaking from some part of the furnace, such as the place where the ducts connect with the unit.

The next time you hear whistling, try to find the source if you can. Even though you can’t necessarily fix the leak yourself, you can give your technician the heads up when you make an appointment for a checkup.

Why Does My Furnace Rattle?

Many people call their HVAC technicians because they hear what seems to be a rattle when the furnace is working. Rattling frequently indicates that at least one part has come loose.

While a rattle may not be a reason to turn off your furnace completely, you don’t want to look the other way, either. Rattles never get better on their own.

Why Does the Furnace Sound Like a Rumbling Train?

Let’s put this out here right now: Furnaces shouldn’t rumble. They aren’t designed to make a rumbling sound when they’re working at peak efficiency.

Usually, a furnace that continuously rumbles hasn’t been cleaned or checked in a while. It may also be starting to wear out if it’s been servicing your home for more than 10 or 15 years.

Why Is the Furnace Making a High-Pitched Squeal?

Screeching, scraping and squealing typically happen when a component in your furnace rubs against another component. For instance, the motor belt may have come loose, or two metal parts might be rubbing against one another.

At the first indication of scraping or high-pitched sounds, turn down the thermostat to shut off the furnace. Wait a few minutes and then turn it on again. If you hear the same noise, call your HVAC provider.

Paying Attention to Your Furnace

All furnaces make some noises. Your job is to listen for any unusual sounds. And if you hear a strange noise coming from the furnace in your Lancaster, PA, home, give Ranck a call for fast, friendly service.

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