Has your air conditioner suddenly developed a new, and rather unsettling, sound? Whether it’s producing a loud clanking noise, a persistent buzz, or a high-pitched squeal, you were wise to pay attention. Ignoring a noisy air conditioner could potentially lead to further problems, such as a complete system breakdown. Simply by recognizing the change in your A/C system’s performance (even if it’s just an unusual sound at the moment), you’re well on your way to resolving the problem and restoring the unit’s functionality.
Oftentimes, the specific type of noise your A/C is making can help a trained HVAC technician pinpoint the root cause of the problem much faster. So, take note of the sounds your system is making, and then give our professionals at Alltemp Air a call for a timely air conditioning repair or maintenance appointment.
Normal Air Conditioner Sounds
It’s helpful to know that there isn’t such a thing as a completely silent air conditioner. A/C units are complex pieces of machinery with many moving parts, and a certain level of sound is a normal part of operation. For this reason, getting familiar with standard air conditioner sounds can save you from unnecessary worry.
If your A/C unit is making any of these sounds, it’s likely in good shape:
- An Initial Clicking Noise: When your thermostat senses that the room temperature has climbed above your set point, it sends a signal to your A/C unit to turn on. This activation is often accompanied by a distinct, sharp “click.” You may hear this from the thermostat itself or from the condenser unit outside. This is simply the sound of electrical components, like relays and contactors, doing their job. A similar click will occur when the cooling cycle is complete and the system shuts off.
- A Gentle Hum: The most common sound you should hear from a healthy air conditioner is a low, steady hum. This is primarily the sound of the large fan motor and the compressor in action. It’s the white noise of summer, a gentle reminder that your system is working to keep your home cool and comfortable.
Problematic A/C Noises That Need Attention
Now, let’s look at the sounds that are cause for concern. These are the unusual, often loud or jarring, air conditioner noises that indicate a problem.
Buzzing
While a low hum is normal, a loud and aggressive buzzing noise is not. This type of sound is frequently linked to an electrical issue within the unit. It could be a failing contactor relay, loose wiring, or a problem with the capacitor, which is a vital component that helps the motors start. In other cases, the fan motor or the compressor itself could be on the verge of failing, creating a distinct electrical buzz as it struggles.
Sometimes, a buzzing or vibrating sound can be the result of refrigerant issues. For example, the copper refrigerant lines may be rubbing against part of the unit, or the refrigerant pressure may be off, causing vibrations in individual components.
Regardless of the source of the buzzing noise, it’s important to turn the system off immediately and contact your local HVAC company to avoid electrical fires and other complications.
Clanking, Banging, or Pounding
These are some of the most alarming sounds an air conditioner can make, and they should be addressed right away. Start by shutting off the system and then call a qualified technician.
A clanking or banging noise often means a part has come loose or broken inside the compressor. This could be a connecting rod, piston pin, crankshaft, or even just a nut or bolt. Allowing the system to run with these internal components loose can cause catastrophic and irreparable damage.
The loud clanking may also be due to loose fan blades in the indoor blower unit or outdoor condenser. When the blades become unbalanced, they can strike other components in the unit. This not only causes a headache-inducing sound but also puts the entire system at risk of further damage.
Squealing or Screeching
A high-pitched squeal is impossible to ignore and demands immediate attention. On some older systems, a worn or misaligned belt that connects a motor to the blower can create a loud squeal, much like you’d hear from a car. More commonly, a high-pitched screeching or squealing sound points directly to failing bearings in the condenser fan motor or the indoor blower motor. This harsh sound is the result of metal-on-metal friction as the bearings wear out completely. Running the system with failing bearings can cause the motor to overheat and seize up, so ask your local technician for help repairing the problem as soon as possible. You may even need to invest in a new A/C installation entirely.
In very serious cases, a loud screaming noise can indicate that the internal pressure in your compressor has reached dangerous levels. Modern systems have sensors that should shut the unit down if this happens, but you should not take any chances. Turn the system off at the breaker and call for emergency service.
Hissing or Whistling
A hissing sound coming from your condenser unit is a classic sign of a refrigerant leak. This is a serious problem, as low refrigerant not only prevents your A/C from cooling properly but can also lead to compressor damage.
Alternatively, if you hear whistling or hissing from your walls or vents, it likely means your home has leaky or improperly sealed ductwork. High-pressure air escaping through a small hole or gap can create an ear-piercing sound and reduce your system’s efficiency.
Persistent Clicking or Ticking
As we mentioned earlier, the initial clicking on and off is perfectly normal, but continuous clicking is not. These sounds often point to an electrical control failure. It could be a failing thermostat that is erratically sending signals or a defective control board that is repeatedly trying and failing to activate the system. Another possibility is a minor fan obstruction. A light, repetitive ticking could be a small object, like a leaf stem, a small twig, or a piece of plastic, that has gotten caught in the fan blades and is striking the protective housing with each rotation.
Don’t Wait — Get Your Noisy Air Conditioner Checked!
If your air conditioner is noisy, don’t try to wait it out. Get it inspected by the expert technicians at Alltemp Air. Our team is trained to interpret these different air conditioner sounds and can get to the bottom of the problem. Whether we need to tighten loose components, replace failing motors, or repair refrigerant leaks, we’ll ensure your system is running safely, efficiently, and without any annoying sounds.
Reach out to our friendly staff today to schedule a service! We’ll help you determine if an A/C repair will suffice or if the sound your unit is producing is a sign you need an A/C replacement.