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Common Reasons Why Your Furnace is Making Noise

Is your furnace suddenly making noises that have you concerned? Normal furnace operation features clicking or tapping sounds as it ignites and turns off. However, when your unit makes strange noises during the entire operation, it indicates an underlying problem. So, why is your furnace noisy?

1. Banging Sounds

A banging sound is commonly a sign of an ignition problem. When the thermostat signals the furnace to start a new cycle, the gas valve opens up. The ignition system should ignite the gas immediately. Sometimes, this process fails due to a faulty ignition system. Some gas leaks into the combustion chamber. When the fuel is finally ignited, the gas in the chamber burns suddenly, creating a banging sound. Be sure to contact a furnace repair professional before this gets any worse.

2. Screeching or Squealing

A loose blower fan can drag its blades against the furnace causing screeching or squealing sounds when the furnace operates. A worn-out or slipping blower belt also makes high-pitched noises during operation.

3. Whistling Sounds

Whistling sounds are a result of the furnace forcing air through blocked components. This may apply to air filters, ductwork, or vents. When cleaning the internal components does not solve the problem, an oversized furnace may be responsible for the noise.

4. Rumbling Sounds

The accumulation of dirt on furnace burners can disrupt the combustion process. When the gas valve is not operating effectively, it will lead to an imbalanced fuel flow. This results in irregular combustion and rumbling sounds. Other times, a flame rollout will cause a rumbling noise. A flame rollout happens when the burner flame extends beyond its designated area.

5. Water Gurgling

This sound indicates problems with the condensate drain. The condensate line carries away water produced during the combustion process. This line may become blocked over time, causing a gurgling sound. Water may also be retained due to improper line sloping, allowing water to pool in certain areas.

If you are uncertain about the cause of the noises that your furnace is making, ask an HVAC expert for assistance. At McFarland Indoor Comfort Services, we provide superior furnace and AC repairs in Granite City and all of Madison and St. Clair Counties. We also offer indoor air quality assessments, custom duct designs, and annual maintenance. Whether you are a residential or commercial building owner, contact McFarland Indoor Comfort Services today and enjoy our fast, friendly, and reliable services.