We aren’t going to say your furnace should never make noise. After all, there’s no such thing as a completely soundless forced air heating system. You’re going to hear it turn on and off, and you’re going to hear the fluctuation of the ductwork as the temperatures change within them. You’ll also hear the air coming through your vents. But the thing about these noises is, you’ll always hear them—from day one.
What we want you to be concerned with is those noises that seemingly crop up out of nowhere—they’re unfamiliar, odd, or loud and unsettling. Some might be quieter than others, and therefore seem not as ominous. But the fact of the matter is, these types of furnace noises shouldn’t be ignored and repairs shouldn’t be delayed. Waiting on repairs of this nature can leave you with a completely broken down furnace right when you need it the most.
So, what noises, in particular, should you be attuned to?
Within your furnace system, there’s a component called the air handler. This component is responsible for circulating air throughout your living space while the system is on. The air handler motor uses a number of oiled bearings to keep friction as low as possible.
These bearings do a great job of keeping friction low. But as a natural part of wear and tear, they wear down over the years. The more worn-out they get, the more friction your furnace’s air handler receives. Eventually, this causes your system to make a grinding noise whenever the furnace is in operation. The bearings will eventually need to be replaced before they fail altogether. Otherwise, the air handler motor can overheat and burn out.
Does it sound like your furnace turns on for a short time, rapidly shut off, and quickly starts up again? This rapid cycling is known as short-cycling, and is both the symptom of a problem and the cause of more problems. Short-cycling can be caused by any number of things that result in heat becoming trapped within the system. We may be looking at an electrical problem, a clogged air filter, or a malfunctioning air handler.
Short-cycling prevents your heating system from warming your living space as well as it should, since your system is designed to operate on set heating cycles. In the long-term, short-cycling can actually cause more problems, increasing the chances of a sudden and detrimental heating system breakdown.
Ensure you call for heating system repairs as soon as you hear or even suspect that your furnace is short-cycling. We would like the chance to help you avoid replacing the furnace prematurely.
Booing is definitely something you never want to ignore when it comes to your furnace system. This is especially true in the case of a gas-powered unit and/or older heating system. This booming sound is very likely due to delayed ignition in the burner assembly, usually associated with carbon particle buildup on the jets. The more particle build up, the longer it takes them to ignite when the system cycles on.
So what happens is that the jets end up igniting late—they have to burn through a large amount of gas at once, and this is what produces that booming noise you hear. Make sure if you detect this furnace sound, that you have a trained and experienced professional clear out the burner assembly.