5 HVAC System Sounds You Don’t Want to Hear

Both packaged units and heat pumps can make unusual noises when something is wrong. That’s why owners should keep their ears on alert. Here are some of the worst sounds your system might make and what they could indicate.

1. Rattling and Clanking

Loose parts in the system, especially in the compressor and blower unit, will rattle. Sometimes, even the compressor can become loose. If the blower fan blades are out of balance, they may give rise to a clanking noise, and if the blades hit against something that’s stuck in them, they may create a “thwapping” sound.

2. Banging

The motor mounts may become loose and start banging. More often, though, the noise results from broken or disconnected parts. That’s why this is a more serious sign than rattling.

3. Hissing and Humming

Humming usually denotes an electrical issue, such as loose wiring. Hissing, though, may signify a leak in the air vents. Owners may come to realize this if they see a sharp rise in their electricity bills. This is because leaks can force the unit to work harder and longer to do its job.

4. Clicking

While clicking is normal when an HVAC system turns on and off, continuous clicking reflects an electrical problem. It could be that the relay or contact (the switch that turns on the compressor, blower motor, or condenser fan motor) is broken.

5. Screeching and Grinding

Bad fan motor bearings can lead to a sound of metal screeching against metal. Screeching can also arise when parts lack lubrication. When fan motor bearings are close to failing, they will produce a grinding noise.

Black Lion Heating & Air Conditioning in Kirkland, WA, has been serving local residents for more than 20 years. We offer heating, cooling, electrical and water heating services. Our NATE-certified technicians can inspect your HVAC unit, pinpoint the issue, and give an accurate, up-front estimate for repairs. To get started, call us today.