Top Air Conditioner Noises To Be Aware Of

image of homeowner trying to sleep but can't due to air conditioning noises

There is no such thing as a fully silent air conditioning unit. Even brand-new cooling systems will emit some sounds that are quite typical for everyday operation. Typically, these noises are caused by regular operation and are not cause for alarm. However, in certain circumstances, an air conditioner making noise may be a sign of a larger problem and should be evaluated immediately by a professional HVAC specialist. Noises are typically indicative of a component or components that are not functioning properly. As a result, the air conditioning equipment may not be operating properly.

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What Types of Air Conditioner Noises Should I Be Aware Of?

Modern air conditioners operate at a far lower noise level than earlier versions. Many versions have noise-dampening technology and variable speed compressors to guarantee AC units operate at a noise level of 55 dB or below. This is the degree of noise produced by a typical dishwasher. If there is a problem with the air conditioning unit, it is likely that it will make one of the following sounds:

The Air Conditioning Unit Is Buzzing

image of air conditioner fan motor bearings

Buzzing air conditioner noises may indicate an electrical problem or misaligned or loose fan blades in the outside condenser unit. Other loose components, filthy condenser coils, or a malfunctioning outside fan motor may also contribute to the buzzing noises. If your air conditioner is leaking refrigerant, it will often make a distinct buzzing noise.

Humming Can Be Heard From The Air Conditioning System

A humming air conditioner may indicate a faulty contactor relay switch. If this component is broken, the air conditioner may not start. The thermostat initiates the outside unit or condenser by sending a signal to the contactor relay switch. This is an electrical issue that should be addressed by a professional HVAC expert. Humming noises can occasionally be produced by issues with the fan motor.

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Clicking Air Conditioner

Clicking noises can be perplexing since they may sound similar to the noise made by the air conditioner when it begins or concludes a cooling cycle. However, if the clicking sound is frequent or persistent, the thermostat may be malfunctioning. If this is the case, it is possible that the thermostat will need to be changed. Ascertain that this is only performed by a licensed cooling professional.

Screeching Air Conditioning Sound

image of outdoor air conditioning unit in summer

A screaming sound is one of the most distinctive sounds produced by faulty air conditioning equipment. The most likely cause of this is a problem with the fan motor on the condenser unit, which is most likely malfunctioning. This fan’s principal function is to remove heat from the refrigerant or coolant. In the event that the fan is damaged, the air conditioner will be unable to cool the interior.

Screeching noises might also be attributed to a broken blower fan motor. Blower fans assist in the removal of heat and humidity from the interior by directing the air to the return ducts, where it is cooled by the air conditioning system. Following that, the blower fan spreads the cold air throughout the home via the air vents.

Additionally, broken fan motor bearings and a faulty fan belt might be causing the AC unit to make squealing noises. If your air conditioner is making a loud screaming or squealing noise, contact an HVAC contractor immediately.

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Clanking Air Conditioner

When your air conditioning system sounds as if a metal component has come free and is colliding with another metal component, you will most likely require a component replacement. Clanking noises might be caused by unbalanced or loose components. If the blades of the outdoor fan or indoor blower become unbalanced or break free, they will collide with other components. This results in the clanking sound. If this is the case with your air conditioner, do not delay in contacting an HVAC specialist. Do not wait for the situation to worsen. Bear in mind that metal-on-metal contact will only result in more damage and expensive air conditioner repairs.

Whistling A/C Unit

image of manometers used for measuring air conditioner refrigerant depicting ac refrigerant leak

Another symptom to keep an eye out for is whistling or a high-pitched noise that sounds as if the air conditioner is screaming. Typically, the noise is caused by a refrigerant leak or a buildup of pressure inside the compressor. Either situation is severe, and it should be handled immediately by a specialist. If this occurs, immediately switch off the unit and contact a local HVAC specialist.

The Cooling System Is Banging

Banging noises are frequently produced by a faulty compressor. These are pretty frequent noises in older central air conditioning systems. The components of the air conditioning machine may become free or unsecured over time due to age and normal wear and tear. Additionally, it is possible that a component of the AC unit is damaged. The piston pin, crankshaft, and connecting rod are all possible components that are found inside the compressor. A skewed indoor blower may likewise result in loud pounding. If this is the case, you will almost certainly require an air conditioning system compressor replacement.

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Whirring Air Conditioning Unit

If your air conditioner sounds as if it contains a drone or, worse, a helicopter, you may have a technical problem such as a defective fan, a faulty fan belt, or a malfunctioning blower fan motor. A whirring sound is produced by a loose fan blade. In the best-case scenario, the issue is just debris stuck in the outdoor fan unit or inside the blower fan. If you are acquainted with the sound made when a sheet of paper is struck by a fan, this is the sound you must deem a warning.

Air Conditioner Is Rattling

Loose material within the exterior condenser unit might cause the air conditioner to rattle. These may contain dirt, fallen leaves, or twigs. This is a simple remedy — simply open the outside unit and clean it out. If the unit is generally in good condition, the sounds might be the result of an issue with the AC electrical contractor. Repair this immediately to avoid more harm.

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With proper air conditioner maintenance and operation, air conditioning units that have passed the manufacturer’s quality test and have been correctly installed can last 15 years or more. However, time eventually catches up with the cooling system, and it may cease to work as well as it once did. If you are unclear about what to do, never presume the situation is straightforward. Contact your chosen HVAC contractor immediately so they can properly diagnose the issue and implement the appropriate remedies.

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Miller Oil Company provides exceptional heating and cooling services throughout Hartford County, Connecticut. We use only the most qualified professionals who are capable of doing superior HVAC tune-ups, repairs, installs, and replacements. Each of our technicians has the necessary expertise and experience to properly service your HVAC system.

Miller Oil Company assures the area’s most reasonably priced heating and cooling service charges. Our services can help to improve your home’s comfort and energy efficiency while also lessening your heating and cooling expenses. If you need HVAC repair or replacement, we can suggest the most cost-effective unit for your home. We guarantee all of our work to ensure your satisfaction. Call Miller Oil Company now to book a service appointment. We provide free in-home estimates.

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