Furnace Making Noise? Here’s What to Do

Woman holding her fingers her in ears to keep out the loud furnace noise.

Is your furnace making noise? If so, you’re not alone. Furnace noises are a common complaint among homeowners and can indicate a bigger problem. 

The good news is that in most cases, furnace noise doesn’t mean you need to replace the unit.  It simply means that something needs to be fixed or adjusted to reduce the noise level. An HVAC tune-up may be just the thing you need.

There could be several causes for furnace noise, and it helps to identify the type of noise you are hearing. Below, we’ll explore some common noises and what they may mean.

Furnace Buzzing Noise

If your furnace is making a buzzing noise, it’s most likely due to an electrical issue. A common cause is a failing blower motor capacitor, which is responsible for powering the blower motor. If the capacitor isn’t functioning properly, it can cause a humming or buzzing sound.

Other possible causes of furnace buzzing noise could include worn-out bearings in the fan motor, loose wiring, or a failing control board.

Solution: If your furnace is making a buzzing noise, it’s best to contact a professional to inspect your electrical components.

Furnace Clicking Sounds

If your furnace is making a clicking noise, it usually indicates an issue with the delay ignition system. One common ignition issue that can cause clicking noises is that no gas is reaching the system due to a faulty ignition board. Bad valves, dirty burners, a broken flame sensor, and an extinguished pilot light (in older furnaces) can also cause problems.

Solution: If you’re hearing a clicking noise coming from your furnace, contact a professional to inspect your fan motor and ignition system.

Loud Banging

Any loud banging sounds coming from your furnace can indicate several problems. Delayed gas valve ignition issues are one possibility. But, it’s also possible that you’re dealing with expanding/contracting air ducts. Or, even a clogged inducer motor could be the issue, as Home Repair Geek explains.

Solution: Contact a professional to inspect your ductwork and furnace ignition system.

Squealing or Whistling

If your furnace is making a high-pitched noise, it may be the result of an issue with the blower. The blower in your furnace is powered by a motor, which has bearings that can wear out because of age or overheating. Overheating is usually caused by dirt buildup or a bad capacitor.

On the other hand, a high-pitched whistling sound is usually the result of a low airflow problem. Low airflow means that the blower fan is struggling to pull in enough air to be heated. This furnace noise can be caused by a dirty air filter, closed or obstructed air vents, or dirty or damaged ducts.

Solution: If you hear any high-pitched squealing or whistling noises coming from your furnace, check your air filter and air vents. If the problem persists after you’ve checked those items, contact a professional to inspect your ducts for any damage or debris buildup.

Furnace Rattling Sounds

Rattling furnace noise can also be caused by loose or worn parts in the furnace. Common loose parts that make a rattling sound include bearings in the blower wheel motor, panels around the furnace, and connections in the ductwork. Worn blower motor fan belts may also create a rattling noise if your furnace is old.

Rattling can also be due to cracks in the heat exchanger, which is a metal coil located inside your furnace. A cracked or damaged heat exchanger can cause noise as well as release dangerous carbon monoxide into your home, so it’s important to have this issue fixed right away.

Solution: If you hear any rattling furnace noises, it’s best to contact a professional HVAC technician immediately. The technician can inspect your heat exchanger for any cracks or leaks and make necessary repairs. Sadly, if your heat exchanger is cracked, the expensive repair cost will be close to that of a new furnace.

Is Your Furnace Making Noise?

If your furnace is making noise, it’s best to not ignore the sound. Rattling, buzzing, or humming noises can be caused by a variety of issues. If you hear this furnace noise, it’s important to have it checked out right away. The most common causes of noise coming from a furnace are either worn-out blower motor parts or a cracked heat exchanger.

If you need help inspecting furnace noise, call Hibdon’s Heat and Air today. Our technicians are HVAC experts and can help diagnose the cause of any furnace noise. Hibdon’s Heat and Air has experience fixing common furnace noises such as rattling, buzzing, or humming. We can also help with more serious furnace problems like a cracked heat exchanger.
Call Hibdon’s Heat and Air today for fast, reliable service and get your furnace running quietly again. Schedule a service today!