If you’ve had your furnace for long enough, you’re probably eminently familiar with the kinds of noises that it makes during operation. What about when it starts making unusual noises, though? Strange furnace noises are some of the earliest and most obvious signs that something is wrong with your system. If you want to be able to call for repairs as soon as possible, and therefore preserve the health of your furnace, you should know what odd noises indicate. Let’s take a look at a couple of the more common noises that indicate a problem below.
Your furnace makes use of a part called the “air handler” to circulate air throughout the home during operation. This part is subject to quite a bit of friction while it’s running, so to compensate it is equipped with a number of lubricated bearings. These bearings help to reduce friction on the system, but wear down over time. If you hear a grinding noise coming from your furnace, it means that the bearings in the air handler motor are wearing down. You’ll need to replace the bearings before the motor overheats and burns itself out.
If you have a gas furnace, as most people do, then you may notice the system making a deep booming noise when it starts up. This is probably because the burner assembly is dirty, causing one or more of the jets to ignite later than they should. When the delayed jets do ignite, they burn through a lot of natural gas at once and create that booming sound. Having the burner assembly cleaned should fix the problem, though it should be done soon. Otherwise, the assembly may eventually get to the point where it doesn’t fire at all.