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Wall Heating & Air Conditioning Blog

These Odd Furnace Noises Are a Warning!


Your furnace will always make some amount of noise. But that noise should be consistent and unsurprising. Basically, you should just hear the usual whoosh and hum. What if your furnace is making other noises? Since your furnace has limited means of communication, you should take any odd noises as a signal: your furnace needs repair! Here’s what the sounds might mean.


Although this is probably something minor such as a loose screw or off-kilter fan blade, you should have it addressed promptly for two reasons. The first is that if the screw or fan blade flies completely free and hits other furnace components, it could do a lot of damage. The second is that there’s a chance the problem is a more serious one, like a cracked heat exchanger, which poses a safety hazard.


This is likely the sound of something rubbing somewhere that it shouldn’t be. Perhaps all the lubricant has worn away—did you remember to have maintenance done this year so everything would be well-lubricated?—in which case it might just be the fan experiencing a lot of friction. It could also be the belt, stretching or tearing or sliding out of position.


Remember that whoosh and hum we mentioned? If you’ve got a gas furnace, think of the way a gas grill ignites: the fuel starts to come out, and then with a woofing sound, it catches fire. If too much fuel comes out before your furnace’s ignition system sparks it, that excess fuel will go up with a bang rather than the usual softer sound. This is a waste of fuel and not ideal for furnace function, so you need heating repair in Suwanee, GA.


This is probably caused by air being forced through a small space, the same way you form a whistle with your mouth. It could be that a seal is loose somewhere in the system, or perhaps there’s a crack in the ductwork. But the first thing you should check is the air filter. If it’s clogged, air being sucked around the edges could make that noise, and you can resolve the problem yourself with a new filter.


Your furnace’s blower fan is powered by a motor, and in order to run smoothly, that motor has bearings inside it. With regular lubrication (remember the maintenance we mentioned?) these bearings can last quite a while, but eventually, they may start to wear down. This can cause a grinding or groaning sound. Get it repaired promptly so you just need to replace the bearings and not the whole motor!


This is a sound to take seriously. If there is loud or persistent clicking, there are two likely reasons for it, and they’re both things that require urgent repair to avoid safety hazards. The first possibility is that there’s an electrical problem, causing a fire risk, and the second is that there’s a crack in your heat exchanger, causing a carbon monoxide poisoning risk. Get help right away!

Reach out to Wall Heating & Air Conditioning, Inc. to make an appointment.

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