Air Conditioner Sounds: What’s Normal?

Lately, it’s seemed like the summers have been getting hotter every year. With the sun bearing down from overhead, your home’s air conditioner unit has never been more important. It’s also getting a lot more use than ever before.

However, not all HVAC systems are meant to run all day without rest. In fact, a unit that never turns off is one of the common problems you can encounter as a homeowner.

A problem that shouldn’t go ignored is odd air conditioner sounds. But what sounds should you expect, and what’s a sign that you need to call in for air conditioner repair in Howell, MI?

Different Types of Air Conditioner Sounds

There are many different air conditioner sounds that are perfectly normal to hear. Your doors might rattle when it turns on, due to a change in air pressure. If you have an outside unit, you might hear it thrumming as it tries to push out the hot air.

If you’ve had your AC system for a while, you’ll notice when things change in any slight way. Maybe you hear a buzzing every now and then or a clicking sound. Or perhaps it’s running noticeably louder than it normally does.

Those sounds may point to a larger problem.

Banging Noises

If you hear banging noises in the night when the AC turns on, it’s most likely a problem with your compressor. The compressor controls all the elements in your unit. It moves the refrigerant around to cool down your home and does most of the work.

Older HVAC systems often develop loose parts that can hit your compressor’s framing. Since these parts aren’t meant to be disassembled, you’ll have to contact your local HVAC companies in Howell, MI or Brighton, MI to correct the issue.


One of the air conditioner sounds to stay aware of is a constant buzzing. This noise can mean the fan blades have loosened. It could also be a sign of displaced parts inside the unit.

In some cases, buzzing can result from a dirty condenser coil or a refrigerant leak. You’ll need to call in air conditioner repair in Brighton, MI to figure out exactly what’s causing the sound.

Hissing or Bubbling

A refrigerant leak in your AC unit can cause a hissing or bubbling sound. Refrigerant can be highly dangerous to humans because they cut off your oxygen supply and are flammable.

If you suspect your HVAC system has a leak, call in for emergency repair as soon as you can.


Some air conditioning units can develop a high-pitched squealing noise due to high pressure. It could result from a malfunctioning belt or a compressor under high levels of pressure.

Homeowners can replace the belt and clean the area around it. As for the compressor, it’ll need to get replaced.


Air conditioner sounds are often the last sign you get of an impending air conditioner problem, like loose fan blades; luckily, the professional HVAC technicians at One Hour Heating & Air Conditioning, here in Howell, MI, can help!
When your thermostat activates your AC unit, you may hear a clicking sound. At the end of the cycle, you’ll hear it again. The click you hear is a result of the electrical relay turning on your unit.

Constant clicking may be your thermostat malfunctioning. It could also happen if your home is leaking out cool air, forcing your air conditioning to overcompensate.


All machines wear down and break eventually, and AC units are no exception. If you start to hear rattling coming from your air conditioner, it’s begun to deteriorate from age. Foreign elements have come loose and are rattling against the inside.

If you hear rattling from your outside unit, there may also be twigs or some other debris trapped inside.

AC Maintenance

One of the biggest air conditioner myths is that your unit doesn’t need regular maintenance. You may think it’s enough to clean out the filter, but there’s a lot more to the machine that needs regular upkeep.

Before you do anything else, always remember to shut off the power so you don’t end up electrocuted. For the outside unit, clean off any debris that has made its way past the fan cage. You can use a vacuum or just your hands to get the job done.

You’ll also need to clean out the fins with a garden hose, spraying away any built-up dirt.

If you have easy access to your inside unit, you can clean the evaporator coil following detailed online instructions. However, it’s easy to mess things up if you have no prior experience. To keep from making things worse, reach out to an expert.

Don’t Ignore New Sounds

New sounds in your home are annoying, and they’re often a signifier that there’s a problem. When you hear new air conditioner sounds, it could be something as simple as a loose bolt or as severe as a refrigerant leak.

Don’t risk your home and your health by ignoring these sounds. Call in for an air conditioner or furnace repair in Brighton, MI, or the Howell area.

One Hour Heating & Air Conditioning services homes throughout all of Michigan, so contact us when your HVAC unit starts to get a little too loud.

When to Seek Heating and Cooling Companies in Howell, MI

It’s easy to not think about AC problems if you live in northern areas, where summers tend to be milder. However, recent heat waves have made things much more dangerous.

In the Pacific Northwest alone, people without air conditioning in their homes are suffering from highs of 112 degrees Fahrenheit. There were even pools closing down because of the heat.

If you start hearing new air conditioner sounds, don’t wait until it becomes a bigger issue. You don’t want to get cooked when your home turns into a giant solar-powered oven.

Try to vet new HVAC contractors before you hire them. Estimating measurements is not acceptable behavior, and neither is doing quick patch jobs. Bad customer service also suggests that they won’t offer good communication or listen to your feedback.

Trust the HVAC Professionals at One Hour Heating & Air Conditioning

If you need help diagnosing the strange air conditioner sounds coming from your unit, then it’s time to call in the pros. For repairing, maintaining, and replacing an air conditioner, there’s no better professional HVAC team in Michigan than One Hour Heating & Air Conditioning. For all a/c maintenance, repair, or new installations, One Hour has you covered.

For the best air conditioner installation and maintenance services, you can’t go wrong with One Hour Heating & Air Conditioning. Give us a call at 800-576-0171 or request your appointment online. For more HVAC tips and tricks, check out our blog. You can also keep up with the latest and greatest deals and news by following us on Facebook and Twitter.