Clanging, Hissing and Rattling: What Six Familiar Furnace Noises Can Mean

When your furnace is running properly, it should provide warm air without making too much noise. While it’s common to catch your furnace making noise as it turns on, other sounds are signaling your furnace needs immediate professional help.

Here are some of the most frequent furnace noises and what they could be signaling. If your furnace is making a weird noise, our friendly heating specialists are here to fix the problem with the best furnace repair in Seymour, Wisconsin.

1. Furnace Makes Banging or Knocking Sounds

You may have a critical issue on your hands if you’re hearing your furnace making a banging noise. If your furnace is making a knocking noise, it may indicate there could be a few problems. These include gas accumulating in your furnace or a ductwork issue.

Banging Sounds Coming from Your Furnace

Your heating system gets grimy over time, so that’s why it’s essential to book routine furnace maintenance with Diedrick's Heating and Air Conditioning. One of the things our technicians perform during this work is clean your furnace’s burners. When this part gets grubby, you could hear your furnace making a loud rumbling noise when ignition takes longer than normal. The resulting gas buildup may crack your furnace’s heat exchanger, where natural gas turns into warmth. Any fractures in it can discharge carbon monoxide, which is ordinarily vented outdoors. This toxic gas can be fatal in large concentrations.

If you’re aware of banging or knocking sounds coming from your furnace, Diedrick's Heating and Air Conditioning urges you to turn it off and contacting us at 920-833-7967. Too much natural gas in your furnace or a ruptured heat exchanger are dangerous troubles that necessitate prompt repairs.

Banging Sounds Coming from Your Ductwork

Your furnace works with ductwork to move heated air across your home. If the ductwork wasn’t installed properly or is getting old, it can make a lot of noise when your furnace is on. This could be the case if your furnace makes a banging noise when it shuts off. Contact Diedrick's Heating and Air Conditioning at 920-833-7967 and we’ll figure out the problem.

2. Furnace Makes a Buzzing Sound

If you hear your furnace making a buzzing noise, don’t hesitate to call us. A buzzing sound typically is telling you there’s an electrical problem, like with its transformer, blower motor or capacitor.

Your furnace uses an internal transformer to run on the right voltage. If wires or the box needs to be tightened, you could notice a low humming noise in the furnace when off. Your furnace also has a blower motor, which distributes hot or chilly air throughout your space, and a capacitor, which starts the motor. If either of these components are fading, they will buzz when the furnace switches on.

3. Furnace Making a Rattling Noise

If your furnace is making a rattling noise, it can be related to something small, like an unfastened screw, or something critical, like a broken part. In either case, we recommend shutting off your furnace and calling our heating specialists at 920-833-7967 for assistance.

4. Furnace Making a Squealing Noise

If your furnace makes a high-pitched noise, like squealing, when it’s heating, it’s trying to tell you it needs some TLC. If you’ve skipped furnace maintenance the last couple of years, belts could be worn out or a bearing could need to be lubricated. We know that maintenance sometimes slips your mind, but our technicians can get your furnace heating quietly again quickly.

5. Furnace Making a Whistling Noise

When you’re detecting your furnace making a whistling noise, it’s likely the result of an air leak in your ductwork. You might also notice whistling while the furnace is running if a floor vent isn’t tight. If you’ve looked at your vents but are still sensing noise, Diedrick's Heating and Air Conditioning can provide support. It’s essential to get loose ductwork fixed quickly, because it can result in comfort troubles in your home and drive up your energy bills.

6. Furnace Makes Noise that Sounds Like Scraping Metal

It’s not an encouraging sign if you detect your furnace making a grinding noise. This metal-on-metal sound frequently means there’s an issue with your furnace’s blower. Switch off your furnace off instantly and reach our pros at 920-833-7967 for help.

When you’re hearing a weird noise from your furnace, Diedrick's Heating and Air Conditioning is available to help. Contact us at 920-833-7967 to book your furnace repair appointment today.