Which Furnace Noises Are Normal, And Which Are Trying to Tell You Something?

Is your furnace making a wonky noise that’s concerning you? The truth is that even healthy furnaces make loud and strange noises, especially during the thick of heating season. You may be wondering if you’re only just noticing a noise that’s always been there or if something has gone very wrong. If you want to get ahead of potential issues, A Guide To Winter Furnace Maintenance covers the preventive steps that can keep small quirks from turning into big problems. Let’s start with noises that probably mean everything is fine.

Why is my furnace so loud? The most common furnace noise people ask about is humming. A low humming noise while the system runs is indicative of normal blower motor operation. Humming only needs attention if you suddenly notice a change in the pace or roughness of the hum. It’s also common to hear a soft clicking before your furnace’s ignition fires and notice some mild popping or pinging as warm air moves through your expanding ductwork.

Again, most furnace noises mean that everything is chugging along seamlessly. However, it’s always smart to make sure you know what any new or unusual sounds coming from your furnace could mean if you skipped furnace maintenance in winter in Indiana this year. Here’s everything you need to know if you notice your furnace making noise.

Strange Noises That Need Attention, But Aren’t an Emergency Yet

Some unusual noises coming from your furnace aren’t emergencies. However, they do indicate that your system needs attention sooner rather than later. Depending on your level of familiarity with your system, that could either mean a DIY check or a professional inspection with an HVAC technician. Here’s the gist:

• Whistling Sounds: Whistling noises or whining could be telltale signs of restricted airflow from a dirty air filter. Luckily, this can be an easy-peasy fix of just checking and replacing your filter. In some cases, whistling could be caused by blocks in your vents or ductwork.
• Rattling: Rattling sounds coming from your furnace almost always point to reverberation from loose panels, a loose screw, loose ductwork, or leaky ductwork joints. The quick solution is to check and tighten the access panel. If you still hear rattling, you may need to have a pro come in to dig deeper for loose connections further in your system.
• Squealing or Screeching: A high-pitched squeal or screeching indicates furnace problems like worn bearings, shaft bearings, ball bearings in the blower motor, or a loose belt on a belt-driven motor. It’s great if you’re catching this early! These problems tend to get worse and cause further damage that gets more expensive over time if ignored. If you’re able, lubricate the moving parts that may be rubbing together. You also want to schedule furnace service as soon as you can, before your blower motor becomes damaged.
• Clicking: If your furnace is making a clicking noise, the ignition system may be faulty. The problem could range from a dirty flame sensor to a broken gas valve.

What Simple Maintenance Can You Do Before Calling a Tech?

Homeowners should definitely try some troubleshooting before calling a tech if they feel comfortable. Things to cover first include:

• Inspect and replace the air filter
• Check that the vents aren’t blocked or closed
• Ensure loose panels on the furnace are fully secured

If the noises stop, you’re probably in good shape until your next appointment for furnace maintenance in winter in Indiana. If humming and rattling persist, quickly book a service appointment to give the problem immediate attention before there’s any further damage.

Furnace Noises That Mean Stop and Call Someone Now

When is emergency maintenance service justified? Indiana homeowners need to know about dangerous furnace sounds that could indicate potential safety hazards. Don’t ignore these furnace sounds:

• Loud Banging: Loud noises or booming at startup are signs of delayed ignition. The background on this is that gas buildup in the combustion chamber is igniting with a tiny explosion instead of a clean light. More often than not, the root cause is a dirty gas burner. These sounds are considered urgent.
• Metal Scraping: That unsettling scraping sound you’re hearing is likely a blower wheel that’s loose or broken. You should stop running your furnace immediately because continuing to let it run is going to cause damage that requires major repairs. Turn off your furnace and call a pro ASAP.
• Persistent Buzzing: Buzzing is usually caused by loose connections, a faulty electrical component, or a failing furnace blower motor. All of these need an immediate professional diagnosis. Buzzing sounds are often neglected just because the furnace is still producing heat.
• Rattling and Heating Issues Together: While we ruled out rattling as a non-urgent issue a little earlier in this article, rattling paired with reduced warm air signals is a serious safety hazard. Most often, this indicates a cracked heat exchanger. If left unchecked, the damaged heat exchanger can let combustion gases mix with your household’s air
• Noises and an Activated Carbon Monoxide Detector Alarm: Consider this a true emergency for carbon monoxide poisoning. The protocol for protecting yourself is shutting off the furnace, evacuating your entire household (pets included), and calling 911. Once safely outside, call a local HVAC professional to let them know what’s happened.

How Can You Tell If a Furnace Noise Is a Potential Safety Hazard?

Don’t ignore any noises accompanied by the smell of gas, visible gas leaks, or a carbon monoxide alarm. These are all emergencies requiring immediate action. Second, pay attention to any unusual noise that comes out of nowhere, is getting louder, or is paired with a heating failure. These all need a same-day call to an HVAC technician to check things out and rule out anything dangerous.

Why Do Older Furnaces Start Making More Noise in Winter?

Indiana’s tough winters put big demand on the heating systems in our homes. This is especially true if you have an aging furnace. For older furnaces, suddenly cranking into action after being essentially dormant since spring can be really taxing. This is one of the reasons why routine maintenance twice a year is such a big help!

The best way to make sure our furnaces don’t fail you in a cold snap is to get things like worn bearings, loose components, and dirty gas burners looked at by September. You will be loving your choice as you enjoy a toasty, problem-free winter at home!

HomeSense’s furnace tune-up service helps you stay ahead of strange furnace noises before they start. Helping homeowners in Central Indiana live their coziest winters without problems since 1961, we’re here for every noise your furnace makes. Reach out today!