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Covenant Heating and Cooling Blog

No, Your Heater Shouldn’t Make These Noises

woman-covering-her-earsThis should be a familiar scenario: you set your thermostat to the desired temperature, wait a few minutes, then hear the fan of your furnace making that familiar whirring sound. The reason it takes a few minutes is because the plenum actually needs to heat up after the burners light before the fan will begin running. Once you hear that whirring, though, you can rely on efficient and effective heat to make its way into your home.

But what if it’s interrupted by another sound entirely? If a sound occurs that you’re not expecting or you have never heard your furnace make before, then it’s time to call for professional heating services in Hendersonville, TN. In the meantime, we’ve provided some guidance below as to what these noises can mean.

Loud Bang or “Boom” at Startup

We’ll start with this sound since it can certainly be the most alarming. If you hear a loud banging noise coming from your furnace consistently, it may have to do with your ductwork or sheet metal siding of the furnace expanding and contracting with the temperature fluctuations. This usually occurs due to poor duct installation or improper furnace sizing, so it still warrants a call.

What’s really concerning, however, is a loud bang or boom during startup. This can be due to a dirty furnace, which may not seem all that serious, but what happens is that the layer of dirt or grime allows gas to build up, and a sort of “mini-explosion” happens when the burners finally do ignite. This may not affect your home right now, but this process rattles the heat exchanger. If that component cracks, then dangerous carbon monoxide gases can and will leak into your home.

Squealing Noise

Any squealing you hear come from your furnace can be the result of a lack of lubrication, or a blower fan belt that is wearing down. This is something that’s a relatively easy fix for our technicians, but that doesn’t mean it’s not a big deal.

If you let this problem go on for too long, the fan can fail, which will stop your furnace from running when you need it the most. It’s better to repair the problem now than wait for a full system breakdown.

Low Rumbling Sound

If you hear a low rumbling noise coming from your system, it’s likely loudest when you’re right next to the unit, right? It’s hard for us to tell you what exactly the cause is, without seeing and hearing the furnace system ourselves. However, one common explanation is that the pilot flame is too low.

Check the flame to ensure it is blue rather than yellow or orange. Otherwise, a rumbling noise can be the sign of a dangerous carbon monoxide leak, depending on the system, so shut it off and call for professional assistance if you believe this to be the case.

We’d encourage you to not take any chances when it comes to the performance and safety of your heating system. Whether you hear one of the above-mentioned noises or some other unfamiliar sound, the best thing you can do for your heater and your home is give our team a call.

At Covenant Heating and Cooling, we are “dedicated to the promise of serving you.” Contact us today!

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