Common Reasons Why Your Furnace Is Making Noise

Located just 20 minutes from Indianapolis, the city of Franklin, IN experiences cold winters that require homeowners to have a reliable furnace to keep warm. However, if you have a furnace that’s making noises like buzzing, banging, or whistling, it can be unsettling. That said, there are a few common reasons why your furnace is making noise, ranging from a blower motor issue to a clogged filter and more. The experts at Dugan Air Heating and Cooling are available to address all of your most pressing furnace concerns, including these unusual and annoying noises. 

Common Furnace Noises and Why They Occur

Here are some of the most common furnace noises and what they mean.

Squeaking

If your furnace squeaks when turning on, it could be caused by a broken or damaged blower motor that hasn’t been cleaned or lubricated. Over time, the belt and blower motor bearings wear down or break, causing the blower wheel to scrape against the housing and produce a strange squeaking sound. If the belt and motor bearings are worn out or broken, it might also create a loud humming or rattling noise. 

Some other causes of squeaking noises coming from your furnace may include:

• A dirty or clogged air filter
• Loose components
• An unbalanced blower wheel

Loud boom or banging

Any sudden, loud booming or banging noises coming from your furnace are certainly cause for concern. This unsettling noise is often caused by dirty burners in your furnace, which should normally light and stay on while the furnace is in operation. However, if the burners are dirty or damaged, gas can build up inside the chamber until the burner ignites, creating a small explosion that creates a loud bang or boom due to delayed ignition. 

Other possible causes of loud booms or banging sounds include:

• Clogged gas lines
• Low gas pressure
• A faulty ignition system

Screeching or whistling

If you notice a furnace screeching noise or if your furnace is making a high-pitched noise like a whistling sound, it could indicate that your filter is dirty or clogged. Furnace air filters should be replaced regularly (typically every 30-90 days) to maintain good airflow and air quality. If your furnace struggles to get enough air through the system, the clogging from excess dust and other debris can produce a nagging screeching or whistling sound. 

Screeching or whistling noises may also be due to:

• An air leak or blockage in the ductwork
• A small leak in the gas line
• Blocked air vents 

Buzzing or grinding

One of the most common problems associated with furnace noise is a buzzing or grinding sound, often caused by loose parts and components like bolts and screws. These parts may become loose or damaged if your furnace is jostled or dropped during delivery or installation, or it may happen over time due to normal wear and tear from constant system vibrations. The issue may get worse as more components loosen, causing more damage that may eventually affect the entire system.

Some other reasons why your furnace is making a buzzing noise may include:

• A failing blower motor
• A faulty capacitor
• Electrical/wiring issues

Furnace Noises That Should Be Addressed Immediately

Although some furnace noises are normal, others should be addressed immediately to prevent further damage to your system. 

• Banging sounds: Loud banging or booming sounds are a sign of a gas buildup and ignition issues that should be addressed as soon as possible.

• Scraping: Unusual metallic scraping sounds might indicate that your blower wheel is malfunctioning, which may lead to further damage if it’s not addressed.

• Whistling: High-pitched whistling noises may be due to a leak in your ductwork or issues with the air intake vent, both of which should be taken care of quickly to improve system functionality and airflow.

• Squeaking: This noise typically means your blower motor and/or blower belt is worn out and needs to be replaced ASAP. 

When to Call for Professional Furnace Repair

Here’s when to call Dugan Air Heating and Cooling for professional furnace repair. 

• Unusual banging, grinding, rattling, or screeching noises come from your furnace and don’t stop
• Some rooms of your home experience uneven heating
• You notice a strong burning smell
• There is a sudden increase in your monthly heating costs
• The furnace won’t turn on or it runs constantly
• You see visible signs of leaks or damage to your furnace
• Your furnace is reaching the end of its lifespan (usually around 15 years old or older) and needs frequent repairs
• The pilot light in your gas furnace is flickering and/or turning yellow instead of blue

Contact Dugan Air Today

Dugan Air Heating and Cooling provides top-quality heating and cooling services to customers in Franklin, IN, and the surrounding areas. Our unique blend of premium service and a fun, no-shenanigans approach allows us to deliver exceptional comfort to your home while providing a memorable customer experience. If your furnace is making noises and needs repair or replacement, contact us to schedule an appointment today!

Frequently Asked Questions

Is it safe to run my furnace if it’s making noise?

If your furnace is making noise, it’s best to turn it off and call for repairs ASAP. Loud banging and booming noises could indicate an issue with the gas supply, ignition, or burners which may pose a threat to your safety. Other noises may be due to a malfunctioning component that should be inspected and repaired or replaced to prevent further damage to your system. 

How do I stop my furnace from squeaking?

To stop your furnace from squeaking, try changing the air filter, inspecting and cleaning the blower motor, or tightening loose parts. If your furnace is still squeaking, call Dugan Air for help.