4 Common HVAC System Noises & What They Mean

Just like a home, heating systems like furnaces, boilers, and heat pumps come with their own noises and clatter, but which ones should you be concerned with if you’re trying to avoid a heating emergency? Recognizing these sounds and understanding what they imply can be crucial in timing your call to an HVAC maintenance professional. This guide will delve into the various sounds your heating system might make and what they could signify.

Grinding or Scraping: Signs of Blower Wheel Damage

The Sound and Its Implications

If your heating system emits a continuing grinding or scraping noise while it is on, it could indicate a problem with the blower wheel. This sound often suggests that the wheel is either damaged, misaligned, or obstructed. The blower wheel is integral in circulating air through your system, and any damage can significantly impact its efficiency as well as your comfort. You may also notice a drop in the amount of hot air coming from your vents, or comfort issues throughout the rest of your home. 

What to Do

If you hear this sound, it’s advisable to turn off the system immediately to prevent further damage. A professional inspection is necessary to determine if the wheel needs realignment or replacement, as it will require exposure to electrical shock risks.

Low Rumbles: Dirty Burners or Pilot Lights

Understanding the Noise

A low rumbling noise from your heating system, particularly common in boilers and older furnaces, might indicate dirty burners or issues with the pilot light. Because burners and pilot lights deal in combustion, issues with these parts can lead to incorrect or incomplete combustion. It‘s important to rule out these issues as soon as possible as they could lead to carbon monoxide exposure or wasting heating fuel. 

What to Do

If your furnace or boiler is making a new low rumbling sound that seems out of the ordinary, it’s essential to call a technician to clean the burners and inspect the pilot light. In some cases, the pilot light might need adjustments or replacement. This is a task to be completed by a professional furnace repair technician.

Loud Thumps or Bangs at Startup

The Causes

Loud thumping or banging sounds during startup can be alarming. These sounds can be caused by several issues:

  • Unbalanced Blower Motor or Wheel: An unbalanced blower can cause significant vibrations, resulting in these sounds.
  • Delayed Gas Ignition: In gas furnaces, a buildup of gas due to delayed ignition can create a small explosion, causing a loud bang.
  • Expanding/Contracting Air Ducts or Heat Exchanger: As the system heats up, the ducts might expand or contract, creating banging sounds.

What to Do

Given the potential dangers, especially with gas buildups, it’s critical to address these sounds promptly. Regular maintenance can prevent some of these issues, but if they occur, professional help is necessary.

Furnace is Silent: Electrical Issues or Thermostat Problems

The Concern with No Sound

Sometimes, the most concerning sound is the absence of one. If you are used to hearing your heating system switch from dormant to active, it could point to an issue with your furnace not getting power.

Troubleshooting and Repair

First, check if the thermostat settings are correct, and that any batteries in your thermostat are freshly replaced. If these are in order and the system remains silent, it’s time to call a technician. Electrical issues can be complex and require professional intervention.

Maintenance & Repair: The Key to a Quiet and Efficient Heating System

If you’re already listening intently to your heating system noises, you’re on the right track to keeping your home heating system maintained and cared for. However, there are a few things you should make sure of each year when it comes to maintaining your heating system, such as: 

  • Cleaning or replacing air filters every 30-90 days
  • Cleaning air vents
  • Pay attention to any recent increases in heating bills

If you notice any of the furnace noises listed above in your Central New York home, call the furnace experts at Energy Savers. 

Call Energy Savers for Heating Repair

Whether you use a boiler, a forced air furnace, or an energy efficient and versatile heat pump, Energy Savers can get it repaired or replaced so you can keep your home warm all winter long. As whole home comfort and efficiency experts, we can also identify other areas in your home that can save energy through home performance upgrades like insulation, window replacement, and more.

Energy Savers is the trusted HVAC contractor near you in Central New York. Call us today at (315) 437-3008.

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