Air conditioners have a lot of moving parts (like motors and fans) that tend to make noise. So, if you hear your AC system start-up or you can hear it softly running, there’s nothing to be concerned about.
However, if you notice that your AC is suddenly louder than normal or is making the following noises, there’s likely an issue.
If your AC is making a Buzzing, Rattling, Grinding, Squeaking or Hissing sounds, there’s an issue with your AC system.
A buzzing noise usually indicates some sort of electrical issue such as a circuit breaker that is failing to trip or bad capacitor.
Debris has fallen into your outdoor unit or a part is loose in your indoor or outdoor unit.
The most likely reason is that some debris, like small rocks, a stick, or some other kind of brush fell into your outdoor unit. Your fan could be hitting this debris and making a rattling noise. If you investigate your outdoor unit and see debris, you’ll want to contact a professional as soon as you can. Debris that’s left in your outdoor unit can damage the internal parts, like the fan, so you'll want to remove the debris immediately. There could be a loose part in your outdoor unit. For example, if your refrigerant pump is loose, it can rattle around in your unit when your AC is on.
If the noise is coming from your indoor unit you likely have a loose part. The same methodology applies here as it does with the outdoor unit. If a part is loose, it can rattle around when the AC is on. Since the indoor unit is typically less accessible than the outdoor unit, it’s safe to say that no matter what part is loose, you’ll want to reach out to a professional for help.
Both your inside and outside AC units have fan motors. If you hear a grinding noise, it likely means the fan motor bearings are bad or need lubrication.
If you think this is your issue, you’ll need to contact a pro to lubricate your fan bearings or make any necessary repairs if your fan is damaged. To prevent this issue in the future, make sure to schedule annual AC maintenance. During a typical AC maintenance visit, a professional will typically lubricate all AC motor bearings (among many other things).
If you hear a squeaking noise, the most likely cause is a loose fan belt in the indoor unit. This can happen if the fan belt has come off the track or if it’s just damaged or frayed due to old age.
To fix this problem, you’ll need to contact a pro to come to look at your system and potentially realign the belt or replace it.
To prevent this issue in the future, you should invest in annual maintenance.
If you hear a hissing or bubbling noise and your AC isn’t cooling your home well, then you probably have a refrigerant leak. The hissing noise is the refrigerant escaping the leak and the bubbling noise is from air that has made its way into the refrigerant lines. If you hear a hissing or bubbling noise, a professional technician needs to fix the leak ASAP. If your AC gets too low on refrigerant, the compressor can become damaged.
If your AC is suddenly louder than normal or is making any of the above noises, contact our team of HVAC experts today.