4 Common HVAC Noises to Know

furnaceHow do you know your HVAC system needs repair or replacement? There are both subtle and obvious ways to tell. When you start to hear unusual noises, this is one of the more noticeable signs it’s time for an inspection. Whether your hear thumping or a loud furnace blower, we identify four common HVAC system noises you should know.

Squeaking

High-pitched screeching commonly indicates a blower motor issue. If something is off with your heating system’s belt, it will make a noise to indicate an issue. Likely, the belt needs to be repaired before the blower completely stops working. When an HVAC technician inspects the motor, the fix may be as simple as the addition of lubricant to stop the squealing noises.

Banging

There are several causes of loud thumping noises. If you hear these sounds coming from the HVAC system, the problem could be:

  • Dirty oil burners, which cause a small explosion when gas is ignited
  • Too much pressure in the air ducts, which causes them to expand and contract
  • A loose blower wheel that’s hitting the blower casing

Rattling

When a component disconnects or breaks, you may hear it clattering around inside the system. An HVAC professional can find the source of the noise and tighten the connection or replace a broken part. If the rattling comes from the compressor unit, the fan motor could be failing.

Clicking

There’s a difference between the sound you hear when the system kicks on and repeated clicking while it runs. One issue could be a dirty flame sensor, which can make it difficult for the system to sense if the gas is lit. If cleaning or replacing the flame sensor doesn’t work, check the compressor start relay for timeout or failure.
 
If you experience any strange noises or need to schedule HVAC maintenance, schedule an appointment with M.J. Fahy & Sons today!