Why Is My AC Unit Making Strange Noises?

Modern energy-efficient central air conditioning systems now come with two-stage or variable speed motors designed to run almost silently. If you hear loud and disruptive sounds from your AC, it's a strong indication that something is wrong.

These noises typically signal a moderate to severe issue, suggesting it might be time for a repair or replacement. To help you pinpoint the problem, here are the most common air conditioner noises you shouldn’t ignore.

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Why is My AC Unit Suddenly So Noisy?

Strange Bubbling Sounds

If your home’s air conditioner is making a bubbling noise, it could be due to excess moisture. This issue often stems from a blockage, crack, or hole in the drainage pipe. If you're handy, you might consider disassembling your air conditioner to inspect the drainage line yourself.

However, replacing the drainage line on your own is not advisable. Fixing the bubbling sound requires specialized tools, equipment, skills, and training that most homeowners don’t have.

For a safe and correct repair, it's best to call a certified technician. They have the expertise to ensure the job is done right, keeping your air conditioner running smoothly.

Constant Rattling Noises

If you’re hearing a rattling noise from your air conditioner, it might just be caused by loose sticks, dirt, or leaves in your outdoor condenser unit. The simplest fix is to disassemble the unit and remove any debris.

However, in a more serious scenario, the rattling noise could be coming from a damaged electrical contractor in your system. This is a more critical issue that needs immediate attention.

If you suspect a malfunctioning contractor, it's crucial to address it promptly to avoid damaging your central air conditioner's compressor. It's best to contact a professional to handle this repair safely and efficiently.

High-Pitched Screeching Sounds

If your air conditioner is making a screeching noise, it’s often due to a malfunctioning fan motor in the outdoor condenser unit. This fan is crucial for removing heat from the refrigerant, ensuring your system runs efficiently.

A shrieking noise typically indicates an issue with the fan motor, but it could also be due to a broken motor in the compressor of the condenser system. Additionally, a damaged blower fan motor inside your home can cause a screeching or squealing noise. This blower fan is designed to collect warm air from every room in your house.

When the blower fan motor is running, it draws hot, humid air through the return ducts and into your air conditioning system, then circulates the cooled air throughout your home. You might also hear a screeching sound from damaged bearings in the fan motor or an impaired fan belt. If you notice a loud AC noise, turn off your unit immediately and call a professional HVAC contractor to avoid further damage.

Unsettling Hissing Noises

If your air conditioner is making a hissing noise, it could indicate a moderate to severe air duct leak in your home. This sound might also be caused by a malfunctioning expansion valve or an incompatible air filter.

It's essential to address this issue promptly. Call a professional to inspect your air conditioning system immediately to prevent further damage and ensure your system runs efficiently.

Loud Banging Noises

If your air conditioner is making a banging noise, it's a clear sign that there's a problem with the compressor. The compressor is crucial for distributing refrigerant throughout the HVAC system to remove excess heat from your home. As your AC unit ages, it's not uncommon for parts within the compressor to become loose.

When these parts become unfastened, you might hear a rattling noise while your air conditioning system is running. This sound is caused by the detached components hitting the compressor’s exterior framing. Unfortunately, compressors are not designed to be easily disassembled, which may mean you need to invest in a new, energy-efficient air conditioner.

If you hear a banging sound from your air conditioner, it's important to act quickly. Contact a local HVAC technician to get professional assistance with this issue and ensure your home stays cool and comfortable.

Persistent Humming Noises

If you start hearing a loud humming noise from your air conditioner, it could be due to a defective contactor relay switch. This essential component kicks the outdoor condenser unit into action when your thermostat sends a signal.

Unfortunately, until this issue is resolved by a licensed technician, you won’t be able to turn on your air conditioner. Ignoring electrical issues in your system can lead to significant problems.

Don’t delay in getting this fixed. Addressing it promptly will prevent severe damage to your central air conditioning system and save you from costly repairs down the line.

Annoying Buzzing Sounds

Never ignore a buzzing noise from your central air conditioning system. This sound could indicate loose or unbalanced fan blades in your outdoor condenser unit. It might also be caused by a faulty outdoor fan motor, dirty condenser coils, or loose components.

A buzzing noise could also signal an obstruction near the copper lines connected to your air conditioner. In the worst-case scenario, it might be a refrigerant leak. Don't ignore this warning sign. Be proactive and prepare for the summer season by hiring a licensed technician to perform an air conditioner tune-up.

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Conclusion

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If you hear an intrusive noise coming from your air conditioner, don't hesitate to reach out to our team. You can call us or book an appointment online. At URBN Home Services, we provide reliable air conditioning repair, tune-up, and installation services for homes in Pennsylvania.

In addition to AC services, we offer a wide range of HVAC solutions, including furnace installation, heat pump tune-ups, boiler replacements, and ductless mini-split installations. Our technicians and managers are trained in the latest heating and cooling techniques to ensure effective and long-lasting results. We are dedicated to your satisfaction and committed to getting the job done right the first time.