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Serving Chester County & Surrounding Areas


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Signature HVAC Blog

5 Warning Sounds from Your Furnace


When do you know you need heating repair in West Chester, PA for your furnace? An easy answer is “when it stops heating.” But if possible, you want to get your furnace fixed before it fails. This isn’t always possible, but furnaces often send out warning signs that something isn’t right. One of the most common warnings you may notice from your furnace are odd noises.

A furnace makes a standard series of sounds when they operate that you’ll come to accept as the background noise of winter: the whoosh of the burners coming on, the whir of the blower motor and fan, the occasional rumble from the ductwork as it expands with the heat. When other noises, either loud or simply strange, break into this soundscape, you may need to call us to investigate and fix the furnace.

We’ve listed below five of the more common furnace noises that will warn you something may be wrong. When in doubt, don’t try to tamper with the system—call us instead. We have fully-trained and NATE-certified technicians to ensure your comfort and safety.

#1. Rattling

This sound can come from a number of sources. The simplest one is an improperly latched cabinet door. However, it could also be from loose components inside the blower assembly, like screws, or imbalanced or dirty blower wheels. Letting these problems continue will only cause more damage to the blower assembly that will eventually lead to the furnace breaking down.

#2. Booming

This is a startling sound, like a louder version of the noise of the gas burners igniting. The cause of this louder boom is usually because of a delay in burner ignition. The sound is the accumulation of unburned gas that suddenly ignites at one time. The burner may be obstructed in some way, such as with dirt or carbon particles, or the problem could be with the ignition system. We recommend you shut off the gas to the furnace and call us to investigate the sound. We may need to repair the ignition system or clean the burners.

#3. Screeching

This is probably coming from the blower motor: its bearings are wearing down, and if they are not replaced, the motor will burn out. The sound can also come from a misaligned motor where the motor housing and blower housing are scraping against each other, eventually causing severe damage to the blower and a more expensive repair.

#4. Grinding

This indicates a more serious motor problem: a motor that’s burning out. The motor usually can’t be saved at this point and you’ll need to have repair technicians replace it.

#5. Clicking

Although you may expect to hear a clicking sound from the igniter when a furnace first starts up, clicking at other times warns of several different problems that will require getting repair technicians involved. The sound could be problems with the gas valves, worn bearings, a loose inducer, trouble with wiring, a broken ignition system, or even cracks in the heat exchanger. You don’t want to guess what’s wrong—leave that job to us and we’ll see your furnace is fixed correctly. 

Call on the Signature Service You Can Trust! Signature HVAC serves Chester County and the surrounding areas.

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