Many homeowners neglect their furnace because it is not out in the open, though there may come a time when the furnace starts making noises that you simply cannot ignore. If you hear any of these 3 noises come from your furnace, consider calling a repair technician to look into it for you.
If you ever hear a scraping sound that is very loud it is an indication that something is not right with the blower wheel. The sound can be similar to metal rubbing on metal or scraping your nails on a chalkboard. This can happen for a couple reasons.
The wheel may have loosened from the furnace's motor shaft, which caused the wheel to rub against the casing. This is an easy repair that can be done by tightening the blower wheel. If your blower wheel became damaged, it would require replacing the part.
There is also a mount inside the furnace that holds the blower wheel in place. A broken mount can cause the blower to shift positions and rub up against the furnace's casing, as well. If you identify this scraping sound, be sure to turn off the furnace immediately to prevent damage from happening to the blower wheel.
You should never hear a banging sound when the furnace turns on. This can be caused by dirt that has collected on the burners, which causes a delay when they try to ignite the furnace. The excess gas that builds up will be what causes the loud bang.
This dirt buildup is due to a filter that needs replacement or cleaning. If you ignore the problem, the small explosion will eventually break the heat exchanger by cracking it. This will be an expensive repair if it happens. You can prevent it from getting to this point by performing regular maintenance on your furnace.
Squealing typically occurs from a blower belt that is loose, which requires the blower belt to be adjusted or replaced. Squealing can also be caused by a malfunctioning blower motor. Once again, turn off your furnace until you can have the furnace inspected. Continuing to run the furnace will lead to the blower breaking down and requiring replacement.
While all furnaces make noises, most are the constant hum of a running blower and small pops in the ductwork. If you're unsure about a sound coming from your furnace, call an HVAC repair specialist to look into it for you.