Especially when you first turn your furnace on in the fall, it may be louder than you expect. So when should you be concerned about the noise?
Well, if you’d say your furnace sounds like an airplane, it’s worth investigating. High pitched whistles and whooshes should not be coming from your furnace. At worst, they indicate a gas leak. At best, the sounds mean that your furnace needs some maintenance. Let’s discuss some common causes of these airplane-like sounds and what you should do about them.
Furnace Sounds Like a Jet Engine
If your furnace sounds like an airplane or jet engine taking off, it’s usually a gas issue. Gas could be leaking from a line or valve. Or, if you hear a click before the swooshing sound, you may have a broken heat exchanger that is leaking gas.
There are other potential causes of this sound. However, as it could be a gas leak, you should reach out for professional help right away instead of investigating the sound yourself. Gas leaks can become emergencies.
Furnace Sounds Like a Train Whistle
Some people associate these high-pitched noises with airplanes, while others think they sound like trains. Either way, there are two common causes of this issue:
- Air leaks: Whistling noises are often caused by air under pressure. When it comes to furnaces, we typically find that a leak in the ductwork is causing the sound. Leaks waste energy, and they can create cold spots in your home, so it’s wise to ask a professional to locate and fix them.
- Blower motor bearing problems: Blower motor bearings may also cause a high-pitched squeal if they are wearing out due to lack of maintenance. Bearings can last longer than furnaces if you keep them in good condition, but if you’ve been skipping furnace maintenance, they could wear out quickly. Depending on the extent of damage, your HVAC professional may be able to fix the bearings or may need to replace them.
Furnace Sounds Like an Airplane in Turbulence
Rattling noises from your furnace may remind you of how airplane turbulence sounds in movies. There are two common causes of this noise:
- Heat exchanger: If your furnace is shaking and rattling, chances are the heat exchanger is broken. As we mentioned above, broken heat exchangers can leak gas and can create emergencies, so it is best to call a professional immediately.
- Loose parts: If you have an electric furnace, or the heat exchanger on your gas furnace is fine, then the noise may be from a loose part that is knocking against another part. Over time, both parts will become more damaged, and eventually, they could break the whole furnace, so it’s best to get this problem looked at as soon as you can.
Why Would a New Furnace Sound like an Airplane?
Most of the time, you’ll only hear airplane sounds coming out of older furnaces. But there are also a few reasons a newer furnace could sound like a jet engine:
- High-Speed Blower Motor
- Modern high-efficiency furnaces often use variable-speed blower motors, which can produce more noise at higher speeds, especially if they’re set incorrectly.
- Solution: Ask your HVAC technician to check if the blower motor speed is appropriate for your home and adjust it if necessary.
- Restricted Airflow
- Blocked or undersized air ducts, closed vents, or a clogged air filter can force the furnace to work harder, leading to a loud noise similar to a jet engine.
- Solution: Inspect and clean or replace air filters and ensure all vents are open and unobstructed. Have a professional evaluate your ductwork for proper sizing and airflow.
- Oversized Furnace
- If the furnace is too large for your home, it may produce excessive noise as it moves more air than necessary.
- Solution: Consult an HVAC professional to assess whether your furnace is appropriately sized for your home.
- Improper Installation
- Poor installation, such as improperly secured ductwork or loose components, can amplify noise.
- Solution: Have the installation inspected by a licensed HVAC technician to ensure everything is correctly secured and aligned.
- Combustion Noise
- A loud noise from the burner or heat exchanger can occur if there’s an imbalance in the gas-to-air mixture or if components are dirty or faulty.
- Solution: Have the burners and heat exchanger inspected and cleaned by a professional.
- Faulty or Loose Blower Wheel
- If the blower wheel or fan is loose or damaged, it can produce loud noises as it spins at high speed.
- Solution: A technician can tighten, repair, or replace the blower wheel if necessary.
- Metal Duct Expansion/Contraction
- If your ductwork is thin or poorly insulated, it may produce loud popping or roaring sounds as it heats up or cools down.
- Solution: Insulate or reinforce the ductwork to reduce noise.
Furnace Maintenance is Key
Regular furnace maintenance will save you’re the hassle of troubleshooting unusual furnace noises in the future. Maintenance is the cheaper option, especially when you consider the repair costs and early replacement costs you’ll face without it.
The good news is that we offer affordable furnace maintenance in Ripon, Lathrop, Manteca, and beyond. Call now to learn more or to get started.
