Five Common Furnace Noises Explained

Man checking furnace

Homeowners in Queensbury, NY, and surrounding cities depend on their furnaces and other heating systems (such as boilers). But when that furnace starts to make strange noises, consider it a cry for help. For a furnace, help is furnace repair or even the installation of a new furnace.

Each noise that your furnace makes could be a symptom of a specific problem, but it’s hard to know what to fix if you don’t know what that problem may be. That’s why Simons Heating & Cooling wants to share with you five common furnace noises and what they mean.

1. Furnace Is Making a Buzzing Noise

There could be multiple reasons why your furnace is making a buzzing noise. Some of the most common include:

  • Dirty or clogged burners: Dirt or debris can build up on the furnace burners, causing them to make a buzzing sound.
  • Loose or damaged parts: Any loose or damaged parts within your furnace, such as the blower fan or belts, can cause buzzing.
  • Blower fan problems: The blower fan might be hitting something in the furnace, causing it to make a buzzing sound.
  • Wiring issues: If the furnace wiring is loose or damaged, it can cause buzzing or humming. Furnaces use a significant amount of electricity and if any of the wiring connections are loose, it can cause buzzing. Loose wiring can also lead to electrical arcing, which can be dangerous and cause damage to the furnace. If you hear a buzzing sound coming from the furnace and suspect it may be due to loose wiring, it’s important to call a professional for repair.
  • Electrical problems: If the furnace’s electrical system is faulty, it can cause a buzzing noise. For example, if the furnace’s blower motor is starting to fail, it can cause a buzzing sound. Other electrical components that could cause buzzing include the control board, the limit switch or the pressure switch. If you hear a buzzing sound coming from your furnace and suspect it’s an electrical issue, it’s important to have a professional diagnose the problem as soon as possible to avoid further damage to the furnace and ensure safe operation.

2. Furnace Is Making a Clicking Noise

The most common reasons why your furnace is making a clicking noise include:

  • Ignition issues: If the furnace is having trouble igniting, it may make a clicking noise when the ignition system tries to start. Common issues with furnace ignitions include a faulty igniter, clogged burners, a malfunctioning control board or a gas supply problem. This can be a tricky issue to resolve, so it’s best to have a professional HVAC technician—such as Simons Heating & Cooling—diagnose and fix the issue to ensure safe and efficient operation of the furnace.
  • Expansion and contraction of metal parts: As the furnace heats up and cools down, metal parts may expand and contract, causing a clicking sound.
  • Loose parts: Loose parts such as screws, bolts or brackets can rattle or make clicking noises as the furnace operates.
  • Dirty or clogged burners: Dirt or debris can build up on the furnace burners, causing them to make a clicking sound as they ignite.
  • Blower fan problems: If the blower fan is hitting something in the furnace, it can cause a clicking sound.

3. Furnace Is Making a High-Pitched Noise

Among the most common reasons why a furnace might make a high-pitched noise are:

  • Loose parts: If any screws or fasteners holding the furnace together have come loose, it can cause a high-pitched rattling noise.
  • Blower wheel problems: If the blower wheel is damaged or out of balance, it can cause a high-pitched noise.
  • Duct problems: If the ductwork is obstructed or has come loose, it can cause a whistling noise.
  • Ignition problems: If the furnace’s ignition system is malfunctioning, it may cause a high-pitched noise.
  • Burner problems: If the burners are dirty or damaged, they can make a high-pitched noise when they’re operating.

4. Furnace Is Making a Popping Noise

A few of the reasons why a furnace might make a popping noise include:

  • Expansion and contraction: As a furnace heats up and cools down, metal parts may expand and contract, causing popping noises.
  • Dirty burners: Dirty burners, such as the buildup of soot, can cause a popping sound as the flame tries to ignite.
  • Ignition issues: If the ignition system is not functioning properly, it can cause a popping noise.
  • Clogged air filter: Your furnace may be making a popping noise due to a buildup of dust and debris in the blower motor. This is often caused by old or faulty filters that fail to properly filter out dirt and other particles from the air. If this is the case, replacing the filters should solve the problem.
  • Loose parts: If any screws or fasteners holding the furnace together have come loose, it can cause a popping noise.

5. Furnace Is Making a Rattling/Knocking NoiseA rattling or knocking noise from a furnace can be caused by a variety of factors, including:

  • Loose parts: If screws or other parts have come loose, they may be making a noise when they encounter other parts of the furnace.
  • Dented or damaged ductwork: Dented or damaged ductwork can cause rattling and knocking noises when air is forced through the system.
  • Blower fan issues: If the blower fan is damaged or imbalanced, it can create a knocking noise.
  • Ignition issues: If the furnace’s ignition system is faulty, it can cause a rattling or knocking noise.
  • Clogged air filter: A clogged air filter can cause reduced airflow, leading to a knocking noise.

Strange Furnace Noise? Call Simons Heating & Cooling Today!

When you have a furnace maintenance plan, a lot of these headaches can be handled before they become a serious issue. If any of these noises sound oddly familiar and you live in Queensbury or another Upstate New York community, give Simons Heating & Cooling a call and we will help solve the problem and return your furnace to the sound you’re use to—blissful silence.

To get your furnace noises solved, call 518-839-2602 today to schedule your appointment!

 

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