Hearing loud noises from your HVAC fan can be concerning for homeowners. However, most of the time, loud fans are a simple fix. When functioning properly, your heating, ventilation, and air conditioning system should operate quietly and go nearly unnoticed. Although only a trained technician that is with your unit can pinpoint the exact issue, I can provide insights into the most common reasons why an HVAC fan could be louder than usual.

A dirty or clogged filter can cause excess noise in an HVAC fan.

A dirty or clogged air filter:

Dirty or clogged air filters are a common cause of increased fan noise. When the air filter is dirty, it limits airflow throughout the system, causing the fan to work harder than necessary, resulting in a louder fan. It is important to know how often you need to change your filter based on its type and your preference. Some filters are more effective in filtering small particles, which means they trap more debris and get dirtier faster. To avoid this, consult your HVAC manual or technician to determine the correct type of filter and how often you need to change it. If the problem persists, and you notice debris building up on your filter too quickly, you may need to clean your ductwork. A clean filter and ductwork are vital to maintaining healthy indoor air quality, system efficiency, and maintaining a quiet system.

Worn motor bearings:

Motor bearings in your HVAC system can deteriorate after years of use, causing the motor to make a humming or buzzing noise. If you hear this noise when the system starts up or shuts down, the motor bearings likely need lubrication or replacement.

Loose or damaged fan blades

Fan blades that have loosened or are damaged can cause the fan to wobble or vibrate. In some cases, these loose or damaged blades can even strike the sides of the unit, causing a banging sound. If you suspect this is the issue, calling an HVAC technician to secure or replace the blades is essential.

The blower motor

The blower motor is responsible for moving air through the ductwork. If there’s an issue with this motor, it can cause the fan to make a loud noise. Common problems include worn or damaged belts, loose or damaged pulleys, or a malfunctioning motor. Any of these issues can result in inefficiency and increased energy bills.

Improperly installed ductwork can cause air to flow unevenly through the system, leading to loud fan noise.Improperly installed ductwork

Ductwork not properly installed can cause air to flow unevenly through the system, leading to noise. If this is the case, the sound will be particularly noticeable in the ducts near the fan, where the noise is amplified. Unfortunately, you may need to have your ductwork repaired or reinstalled.

It is important to have a trusted HVAC technician inspect your system if you are experiencing a noisy HVAC fan. A trained professional can determine the cause (or causes) of the problem and the best course of action to fix it.

If you need a repair, you can contact us here. If you are considering replacing your furnace, you can get an estimate now!

We hope you found this article helpful and look forward to continuing to ensure your comfort and safety. Thank you for choosing CPS.

If you are in need of more information or would like to schedule a free consultation, you can reach us at 508-460-6691 or fill out this form.

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