Categories: Homeowner's Corner

8 Common HVAC Noises, Explained

Have you ever heard noises in your home? Likely, the answer is yes. Home appliances like dishwashers and laundry machines often make strange noises.

One place you don’t usually expect to hear strange noises from is your HVAC.

Like other appliances, your HVAC system sometimes talks back. You can expect normal functioning sounds, but sometimes you get more than a quiet background hum.

Keep reading to learn what your HVAC noises mean and when to seek professional help.

Common HVAC Noises

An HVAC system operates through a network of air ducts within your house. While those air ducts push air to each room of your home, they also echo noises throughout your house if something is wrong.

1. Squeezing and Screeching

If you hear a squealing sound with your system starts up, it probably means you need to replace a belt or motor bearing. Depending on how loud of a screech you’re hearing, the solution could be as simple as lubricating the problematic belt.

If some WD-40 doesn’t fix the problem, then contact a professional to avoid bigger issues down the line.

2. Rattling

An easy enough fix, rattling typically means there’s something in your vents being blown around. That could be a small nail or some other debris.

First, try to pinpoint the location of the sound. Unscrew the vent cover and try to find the debris. If you cannot find the debris, and the rattling persists, then you should contact a specialist.

3. Popping

If you just turned on your heat for the first time in a while, you may hear a popping noise coming from your air ducts. This is a common sound. The rush of warm air against the cold metal material causes the air ducts to expand.

You may experience this popping noise from time to time when using heat. If you hear a popping noise and you’re not using heat, then you should reach out.

4. Clicking

When you turn on your furnace, a quick clicking sound means it’s working properly.

If you hear a clicking sound even when the furnace is off, or the clicking sound is all the time, contact a technician to reach the source of the problem. There may be an issue with the furnace igniting.

5. Booming

Like clicking, a booming sound comes from the furnace. But, unlike clicking, this sound means that your furnace isn’t lighting. It could mean that your propane line has a build-up and needs cleaning.

6. Buzzing

Buzzing is a rather normal sound to experience from your HVAC system. It usually means there’s a loose part vibrating or compressor malfunction. If the sound persists, it wouldn’t hurt to have someone take a look at it.

7. Thumping or Banging

A banging noise is never welcome in HVAC systems. The noise likely comes from your blower assembly.

If something big is stuck in the fan, it results in a banging noise. To avoid a bigger issue, turn off your A/C and call a technician.

8. Hissing

Another unwelcome sound to hear in your home, hissing can signal a couple of things. Most likely your A/C or your furnace is leaking. Either your A/C is leaking refrigerant or your air ducts have an air leak.

Both issues can cause higher energy bills and eventually more problems. Again, your best idea is to get it checked by a professional.