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

October 13, 2020

When your furnace is working properly, it should give warm air without creating too much disruption. While it’s expected to hear your furnace making noise as it turns on, other sounds are showing your furnace requires immediate professional support.

Here are some of the most common furnace noises and what they can be indicating. If your furnace is making a strange noise, our friendly heating pros are here to assist with the best furnace repair in San Jose, CA.

1. Furnace Making a Banging Noise

You might have a serious issue on your hands if you’re detecting your furnace making a banging noise. If your furnace is making a knocking noise, it might signal there could be a couple of problems. These range from gas accumulating in your furnace or a ductwork issue.

Banging Sounds Coming from Your Furnace

Your heating system becomes filthy over the years, so that’s why it’s essential to schedule annual furnace maintenance with American HVAC Inc. One of the jobs our technicians do during this service is clean your furnace’s burners. When this part gets grubby, you could hear your furnace making a loud rumbling noise after ignition takes more time. The resulting gas buildup may break your furnace’s heat exchanger, where natural gas transforms into warm air. Any cracks in it can discharge carbon monoxide, which is ordinarily released outside. This dangerous gas can be deadly in large concentrations.

If you’re noticing banging or knocking sounds coming from your furnace, American HVAC Inc recommends turning it off and contacting us at 408-215-1018. Excessive natural gas in your furnace or a fractured heat exchanger are serious issues that require immediate repairs.

Banging Sounds Coming from Your Ductwork

Your furnace works with ductwork to provide heated air throughout your residence. If the ductwork wasn’t installed right or is getting dated, it can make a lot of noise when your furnace is on. This may be the problem if your furnace makes a banging noise when it shuts off. Contact American HVAC Inc at 408-215-1018 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 is telling you there’s an electrical problem, like with its transformer, blower motor or capacitor.

Your furnace depends on an internal transformer to run 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 uses a blower motor, which sends warm or cooled air around your space, and a capacitor, which triggers the motor. If either of these parts are fading, they will buzz when the furnace starts.

3. Furnace Making a Rattling Noise

If your furnace is making a rattling noise, it could be due to something little, like an unsecure screw, or something critical, like a broken part. In either case, we urge you to shut your furnace off and calling our heating professionals at 408-215-1018 for help.

4. Furnace Making a Squealing Noise

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

5. Furnace Making a Whistling Noise

When you’re detecting your furnace making a whistling noise, it’s likely because of an air leak in your ductwork. You may also hear whistling while the furnace is working if a floor vent isn’t secure. If you’ve checked your vents but are still hearing whistling, American HVAC Inc can assist you. It’s essential to get loose ductwork taken care of without delay, as it can result in comfort problems in your house and increase your energy bills.

6. Furnace Making a Grinding Noise

It’s not a good sign if you detect your furnace making a grinding noise. This metal-on-metal noise frequently means there’s trouble with your furnace’s blower. Shut down your furnace off now and call our professionals at 408-215-1018 for support.

When you’re noticing an uncommon noise from your furnace, American HVAC Inc is ready to provide assistance. Contact us at 408-215-1018 to book your furnace repair appointment right away.