Why Is My Heater Humming? 3 Common Reasons – Dial One Sonshine
A technician inspecting a furnace

While it’s true that no heater operates silently, some sounds should definitely be checked out by a professional. One of those odd noises is humming, which could be a sign of a system failure in your near future.

Below are the most common reasons why heaters produce a humming or vibrating sound.

1. Some Parts Are Loose.

If your furnace hasn’t received preventative maintenance in a while, its components might need some tightening. Like any machine, a furnace accumulates wear and tear over time, and its parts can loosen and start to move around and vibrate against each other. This can create a humming noise whenever your heating system runs.

Your system’s metal air ducts can also be the source of the noise. Over many years, the metal can expand, contract, and loosen, so it’s possible that the humming is actually vibrating ductwork that needs to be readjusted and sealed or replaced altogether.

2. There’s A Problem With The Blower Motor And Capacitor.

What exactly are the blower and capacitor? The blower is the part of your furnace that blows hot air through your ductwork and into your home. The capacitor stores energy (kind of like a battery) and provides the necessary burst of energy to get the blower motor spinning.

If your heater hums when the blower starts to slow down (after heating your home for a while), this usually means that there’s an issue with the capacitor and blower motor. You can also tell that there’s a capacitor problem if the blower motor is humming but won’t turn. Typically, replacing the damaged capacitor solves this issue. If the motor overheated at some point, you might also need to reset it.

3. The Transformer Module Is Making Noise.

Your heater’s transformer reduces your house’s voltage to a level that your furnace can safely use. The transformer also helps protect your HVAC unit from energy spikes that could damage its circuitry.

As this component operates, it can produce a humming sound. Although the sound can be annoying, the good news is that it usually doesn’t indicate a problem with the transformer. You can try to prevent the noise by tightening the hold-down bolts, or you can ignore it. Sometimes the hum will even disappear on its own.

Reliable Heater Repair In Orange County

When your heater starts making odd noises, it’s best to involve a professional to get to the root of the problem before it gets worse. Contact the HVAC experts at Dial One Sonshine today online or by phone: (714) 613-1016.

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