Banging, Screeching and Rattling: What 6 Typical Furnace Noises Indicate

October 13, 2020

When your furnace is operating properly, it should deliver heat without generating too much disruption. While it’s common to notice your furnace making noise as it starts up, other sounds are indicating your furnace should get 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 professionals are here to fix the problem with the best furnace repair in the Bay Area, CA.

1. Furnace Making a Banging Noise

You might have a serious problem on your hands if you’re noticing your furnace making a banging noise. If your furnace is making a knocking noise, it can mean there could be a few problems. These include gas building up in your furnace or a ductwork issue.

Banging Sounds Coming from Your Furnace

Your heating system turns dirty over time, so that’s why it’s critical to book annual furnace maintenance with Contra Costa Heating & AC. One of the things our professionals perform during this service is clean your furnace’s burners. When this part gets grimy, you might hear your furnace making a loud rumbling noise when ignition takes longer than normal. The following gas buildup might crack your furnace’s heat exchanger, where natural gas changes into heat. Any breaks in it can emit carbon monoxide, which is normally released outside. This dangerous gas can be deadly in large concentrations.

If you’re hearing banging or knocking sounds coming from your furnace, Contra Costa Heating & AC recommends turning it off and calling us at 510-343-9841. Too much natural gas in your furnace or a ruptured heat exchanger are hazardous problems that should get prompt repairs.

Banging Sounds Coming from Your Ductwork

Your furnace relies on ductwork to move hot air around your home. If the ductwork wasn’t installed properly or is getting dated, it can be loud when your furnace is heating. This can be the issue if your furnace makes a banging noise when it shuts off. Call Contra Costa Heating & AC at 510-343-9841 and we’ll figure out the problem.

2. Furnace Making a Buzzing Noise

If you hear your furnace making a buzzing noise, don’t delay calling us. A buzzing sound often means there’s an electrical issue, like with its transformer, blower motor or capacitor.

Your furnace relies on an internal transformer to operate on the proper voltage. If wires or the box is loose, you could notice a low humming noise in the furnace when off. Your furnace also works with a blower motor, which moves warm or cold air around your rooms, and a capacitor, which starts the motor. If either of these pieces are fading, they will buzz when the furnace turns on.

3. Furnace Making a Rattling Noise

If your furnace is making a rattling noise, it might be due to something little, like an unsecure screw, or something major, like a broken part. In either case, we advise shutting your furnace off and contacting our heating specialists at 510-343-9841 for support.

4. Furnace Making a Squealing Noise

If your furnace makes a high-pitched noise, like squealing, when it’s running, it’s trying to get your attention it requires some TLC. If you’ve skipped furnace maintenance the last couple of years, belts could be dilapidated or a bearing may need to be lubed. We are aware that maintenance often slips your mind, but our technicians can get your furnace heating quietly again fast.

5. Furnace Making a Whistling Noise

When you’re hearing your furnace making a whistling noise, it’s typically due to an air leak in your ductwork. You may also notice whistling while the furnace is operating if a floor vent isn’t secure. If you’ve examined your vents but are still hearing sound, Contra Costa Heating & AC can provide support. It’s important to get loose ductwork repaired fast, since it can result in comfort problems in your residence and drive up your utility costs.

6. Furnace Making a Grinding Noise

It’s not an encouraging sign if you detect your furnace making a grinding noise. This metal-on-metal racket usually means there’s a problem with your furnace’s blower. Switch off your furnace off promptly and reach us at 510-343-9841 for assistance.

When you’re noticing a strange noise from your furnace, Contra Costa Heating & AC is ready to support you. Contact us at 510-343-9841 to schedule your furnace repair appointment today.