Are the noises coming my AC normal? 10 weird noises your AC is making and why.

air conditioners

The last thing you want to hear when you turn on your air conditioning on a hot Oklahoma day is an odd sound coming from your vents or the air conditioning unit itself. But if you aren’t mechanically inclined or familiar with central AC noises, you might be wondering whether the sound you’re hearing is normal or evidence that you need to call a professional to check your system out.

Here’s a quick breakdown of the different sounds an AC can make, and which ones you can immediately forget about versus which ones you should be on the lookout for.

NORMAL SOUNDS YOUR AIR CONDITIONING CAN MAKE

If your cooling system is making one of the sounds described below, you can breathe a little easier—it’s likely operating as intended!

WHOOSHING

If you hear your air conditioner make a sound like a plane taking off when it first kicks on (only not as loud, obviously), that’s normal operation! Air conditioners have a lot of moving parts, and there will be a brief series of startup-related sounds.

CLICKING

It’s also normal if your AC clicks once or twice right at the end of the cycle, before powering down—this is the sound of the different machinery coming to a stop.

If you hear your cooling system click when it first kicks on and turns off, there’s no need to worry, as this is normal operation. But continuous clicking during operation can signal an electrical malfunction, which can be very dangerous in a home. It could be a malfunctioning control or issue with the thermostat.

LOUD OUTDOOR UNIT

If your outside AC is making loud noises, it might not be a sign of an air conditioner that’s broken or in need of repair, but simply an older, aging model. You might not even be able to hear it inside your home, but it’s probably not your neighbor’s favorite sound to listen to. While a loud outdoor unit likely isn’t cause for concern, it is a good sign that you could benefit from an AC upgrade—today’s cooling system models, from central AC to ductless mini-splits, are not only much quieter but more energy efficient as well, saving you money.

AC SOUNDS THAT COULD BE THE SIGN OF AN HVAC PROBLEM

Hearing any of the sounds below? Our recommendation is to call an HVAC expert to take a closer look at your air conditioner and make sure there isn’t an issue that needs repairing.

BUZZING

A buzzing noise coming from your air conditioner could be caused by several issues, including:

  • Loose parts vibrating
  • An issue with the condenser fan
  • Electrical problems
SQUEALING

Is your AC making a constant high-pitched squealing noise? It could be an issue with the bearings on your condenser motor, or a belt issue if your unit is an older model.

PULSATING

A pulsating noise from your outside air conditioner unit might not be cause for concern if it’s at a low volume, but if it’s loud enough that you can hear it inside, the coil fan or motor fan blade could be to blame, and you’re better off getting it checked by a professional.

WHISTLING

If you’re hearing a whistling sound from your HVAC system, it’s likely coming from your vents. Whistling noises are primarily caused by airflow issues. This could signal that it’s time to check your air filters to see if they’re completely clogged and restricting airflow through your ductwork! Not only can this be annoying to listen to, but it can add unnecessary wear and tear to your AC itself and lead to more frequent AC repair calls.

HISSING

Hissing (or worse, a high pitched shrieking) is one of the signs that you have a refrigerant line leak. Refrigerant leaks can not only cause serious damage to your unit—it can cause health problems for the people inside your home. Turn off your air conditioning system immediately, and call a professional HVAC technician for a closer inspection.

POPPING/CRACKLING

If your AC unit is making a popping noise, it could be as a result of ice forming, either because the temperature is set too low or because of water drainage issues. If water can reach some of the more sensitive areas of your system, it could cause lasting (and expensive) damage.

RATTLING/BANGING

Rattling, clanging, or banging noises coming from your air conditioner are often due to a loose part or screw. It could also be from stuck leaves or debris, or a loose fan blade

For many Oklahomans, it’s hard to resist the urge to bury your head in the sand when your air conditioning starts making strange sounds. Among other common excuses:

  • “OH, IT’S NOT THAT LOUD.”
  • “WELL, THE AC IS STILL WORKING, SO HOW BAD COULD IT BE?”
  • “I CAN’T HEAR IT WHEN I’M UPSTAIRS, SO MAYBE I’LL JUST SPEND MORE TIME UP THERE…”

We’re right there with you—having to deal with an unexpected problem with your air conditioner can be a headache, and you could be worried about the unexpected cost of AC repair. But trust the cooling experts at DeHart Air Conditioning—when your AC is making a noise it doesn’t usually, the time is act is now! Here are a few of the more commons sounds you might be hearing, and what could be going on with your AC.

SCHEDULE REPAIR OR AC MAINTENANCE WITH DEHART TODAY

The thing to remember about weird AC noises is that it’s always better to catch the problem early on. It will be much less expensive to identify and address a small problem than to wait until your cooling isn’t working anymore and your AC is blowing warm air before finally calling an HVAC company for emergency repairs.

In fact, the best way to avoid costly air conditioner repair in your Duncan, OK home is to schedule seasonal HVAC maintenance. A tune-up for your air conditioner (or furnace) will help ensure that your system is in the best position to provide high efficiency operation all year long. Take it from the AC repair experts at DeHart—our customers who call us every spring and fall for HVAC maintenance pay far less than the customers who call needing immediate repair because their AC won’t turn on and end up needing AC replacement.