When operating properly, your HVAC system should be fairly quiet. Even if your furnace has been working well this winter, if you start hearing one of these strange sounds, it is time to contact an HVAC professional to come and repair the problem.

Here are 5 sounds your furnace can make that should be taken care of as soon as possible before they turn into larger issues.

Scraping Sound

A loud scraping, metal-on-metal sound coming from inside your furnace could be a serious problem with the blower wheel. It is possible the wheel is coming apart from the shaft and scraping the casing. Turn your unit off and call in a professional to solve this issue.

Fast Clicking Sound

Remember that sound when you were a kid and attached a playing card to the spokes of your bicycle wheel? If you hear that kind of fast clicking sound from your furnace, something might be stuck on one of the blower wheel blades or the housing around the wheel. While your heat may be working just fine, this stuck object causes resistance which can result in excessive wear on the motor.

Squealing Sound

A squealing noise from the blower motor could be caused by a belt wearing out. This is a relatively easy fix that is best to take care of sooner rather than later before the belt stretches further or breaks.

Grinding Or Metal Groaning Sound

A bearing problem in the blower motor will make a dull repetitive groan. Some blower motors have ports for adding lubricant, but some are sealed. Adding lubricant will often eliminate the groaning sound, but you have to use the correct oil.

Popping Sound Or Banging Sound

If you hear popping or banging when firing up your furnace, the problem is likely dirty burners. If your burners have not been cleaned recently, gas is not being ignited by the furnace right away. Instead, it builds up and ignites in a mini “explosion” which is what causes the distinct popping or banging sound. This should be serviced by a professional immediately.