AC Making Noise – Causes, Fixes, and How to Prevent It

Are you experiencing issues because your Air Conditioner is making noise? Well, you’re at the right place. An air conditioner making noise can be frustrating and sometimes indicates that something is wrong. A normal AC will produce a slight humming sound when in use. However, if your AC makes loud and constant noise, this might be a sign that something is wrong. Air conditioner noise can be caused by loose parts, air flow issues, or other internal damage.

It is essential to understand the causes of AC noise because this will help you avoid costly repairs. In this blog, we will explain to you the different types of air conditioner noise, the causes of AC making noise, and how you can fix your air conditioner when it makes noise.

Common Types of AC Noises and Their Meanings

Different types of sounds coming from an air conditioning unit usually mean different things, such as:

• Buzzing Noise – The buzzing noise usually means there is a loose electrical part, debris in the outdoor unit, or a faulty compressor.
• Clicking Sound – The clicking noise is usually heard when the air conditioner starts or stops. However, it could mean that there is a problem with the relay or thermostat if it persists.
• Banging Noise – The banging noise usually means that there is a loose or broken internal part of the air conditioner, like the compressor or fan.
• Hissing Sound – The hissing noise usually means there is a leakage of refrigerant or internal pressure problems.
• Grinding Noise – The grinding noise usually means there is a worn-out bearing in the motor of the air conditioner.
• Whistling Noise – The whistling noise usually means there is a restriction of airflow in the ductwork, as well as a clogged air conditioner filter.
• Rattling Sound – The rattling noise usually means there is a loose screw, debris, or a damaged fan in the air conditioner.
• Squealing Noise – The squealing noise usually means there is a belt or motor problem.
• Dripping or Gurgling Sound – Water drainage problems might cause this air conditioning unit noise. If you notice water leaking too, read our guide on how to fix water dripping from split AC indoor unit.
• Cracking Sound – This usually occurs when there is expansion or contraction of plastic parts due to temperature changes.
• Split AC Indoor Unit Making Noise – This might be caused by fan imbalance, loose front panel, or obstruction of airflow.

Causes Behind Noisy AC Units

There are various reasons behind the noisy air conditioners. Knowing the reasons is helpful in solving the issue faster.

• Loose Parts – The screws and panels inside the air conditioners may become loose over time.
• Clogged Air Filters – The air filters inside the air conditioners may become dirty and clogged. As a result, the sound produced by the air conditioners may become louder.
• Fan Problems – The fan blades inside the air conditioners may become damaged and dislocated. As a result, noise is produced.
• Refrigerant Leak – The hissing sound produced by air conditioners may be due to a leak in the refrigerant lines.
• Debris in Outdoor Unit – Debris falling into the air conditioners may cause noise while rotating the fan.
• Worn-Out Motor Bearings – Old motors can cause grinding or squealing noises.
• Improper Installation – An AC that was not properly installed could cause the AC to vibrate and result in a noisy aircon.
• Blocked Drain Line – Water buildup could cause bubbling noises.

How to Fix AC Noise

Here is a table showcasing quick fixes when your AC makes noises:

AC Noise Type	Quick Fix
Buzzing	Clean the outdoor unit and check for loose electrical components.
Clicking	Restart the AC and check the remote or thermostat settings.
Banging	Turn off the AC immediately and call a technician for inspection.
Hissing	Contact AC service to inspect refrigerant lines and pressure levels.
Grinding	Stop using the AC and get the motor bearings checked by a professional.
Whistling	Clean or replace clogged air filters to improve airflow.
Rattling	Tighten loose screws, panels, or internal components.
Squealing	Schedule professional servicing to inspect the motor or belt.
Dripping	Clean the drain pipe and ensure proper water drainage.
Gurgling	Check the drainage line and remove any blockage.
Cracking or Popping	Usually normal due to temperature changes; monitor if it becomes frequent.
Split AC Indoor Unit Noise	Tighten the front panel and clean filters or fan blades.

How to Fix a Noisy AC

Fixing a noisy air conditioner varies depending on the type of air conditioner and the cause of the noise.

DIY Fixes

There are some air conditioners making noise problems that can be fixed at home, like:

• Clean or Replace Air Filters – The air conditioner making noise at home could be due to unclean air filters. The air conditioner works by blowing air, and when the air filters are unclean, it could cause noise.
• Tighten Loose Screws and Panels –  The air conditioner making noise could be due to loose screws and panels. Tighten all loose screws and panels to fix the problem.
• Remove Debris from the Outdoor Unit – This usually includes leaves, dust, and other materials around the fan.
• Check the AC Placement – It is important that the AC is placed on an even surface.
• Clean the Fan Blades – This happens when dust gathers on the fan blades.
• Inspect the Front Panel – A loose panel can be the cause of rattling sounds.

Professional Repairs

When the AC unit is noisy despite the basic checks, professional repair may be necessary, especially when:

• Motor or Fan Replacement – When the AC unit’s motor or fan is damaged, they need to be professionally replaced.
• Compressor Repair – When the AC unit makes loud banging noises, the compressor may be damaged and in need of repair.
• Refrigerant Leak Repair – When the AC unit makes hissing sounds, the refrigerant leak may need to be professionally detected and repaired.
• Electrical Component Fix – When the AC unit’s relay or capacitor is damaged, the clicking sounds may need to be professionally fixed.
• Internal Part Replacement – When the AC unit’s internal parts are damaged, they may need to be professionally repaired.

You should make sure that you use trusted professional services like NoBroker to handle your AC repairs.

Preventive Measures

Regular maintenance can help in the prevention of your AC’s making noise problems.

• Schedule Regular AC Servicing – Regular professional cleaning of the AC keeps internal parts of the AC clean and helps in the smooth running of the AC.
• Clean Air Filters Monthly – Regular cleaning of the air filters can help in the air flow and reduce noise.
• Keep the Outdoor Unit Clean – Cleaning of the outdoor unit often and removing leaves, dust, and debris will prevent the fan from making sounds.
• Check Mounting and Installation – Proper mounting and placement reduce the chances of the unit making vibration sounds.
• Inspect Components Periodically – Regular checks can help in the prevention of air conditioner sounds.

When Noisy AC Signals Can Become Bigger Problems

Sometimes, a noisy AC unit could be a sign of serious problems. Here are some warning signs you must know:

• Very loud banging or grinding sounds.
• The AC unit is performing poorly.
• Burning smell, together with noise.
• AC unit is frequently shutting down.
• Continuous hissing or bubbling sounds.

When these problems, aside from the noise, occur, it is best to contact professionals like NoBroker immediately.

Split AC vs Window AC Noise Levels

There is a difference between Split AC and Window AC Noise Levels, such as:

• Split AC – Relatively quiet since the compressor is external.
• Window AC – Slightly louder since all the equipment is contained in one unit.

The installation of air conditioning units minimizes noise from air conditioning units.

Signs Your AC Needs Cleaning

• Less Cooling- If your AC is taking longer to cool the room or it is not cooling to the desired temperature, it could be due to clogged filters and dirty coils which might be stopping the airflow.
• Unpleasant Smell from the AC- If there is a musty or unpleasant smell from the AC, it could be due to mold, bacteria, or dust gathered in the filters or drain tray.
• Water Leakage from Indoor AC Unit- If there is water leakage from the indoor AC unit, it could be due to clogged drain pipes or high dirt accumulation.
• Rise in Electricity Bill- If your AC is working harder due to dirt gathered, it could result in a significant increase in your electricity bill.
• Dust Coming Out of the Vents- If you notice dust particles coming out along with the air, it is a sign that the filters and internal parts require immediate cleaning.
• Unusual Noise while Operating- If you notice unusual noise while operating the AC, it could be due to dirt gathered in the blower or internal parts, which require immediate cleaning.

If you are experiencing any of these symptoms, it is recommended that you book professional AC cleaning services from companies like NoBroker to get back to smooth cooling performance.

Cost of Fixing a Noisy AC in India

Here is a basic cost for fixing noise problems in your AC:

Service Type	Estimated Price
Fan & Blower Noise Fix	₹1,500 – ₹3,000
Outdoor Unit Noise Fix	₹1,800 – ₹3,500
Loose Parts Tightening	₹300 – ₹800
Vibration Issue Repair	₹500 – ₹1,500

The cost of fixing your noisy AC may vary depending on the type of repair required and your location.

AC Noise Level in Decibels (dB)

The AC noise level is given in decibels (dB). The decibel level of the AC noise varies from one air conditioner to another. 

Split AC Indoor Unit (19-35 dB) – Extremely quiet running, similar to whispering. Loud sounds of the air conditioner may be due to fan or airflow problems.

Split AC Outdoor Unit (45-60 dB) – Normal air conditioner noise from the compressor and outdoor fan unit.

Window AC (50-70 dB) – Slightly louder than the above AC models, as all the parts are in the same unit.

If the AC noise level is higher than the above-mentioned decibel level or has unusual sounds like buzzing, grinding, or rattling, the noisy AC unit may need attention.

Conclusion

It is not a good idea to ever ignore an AC that makes noise because it could be a sign of a mechanical or airflow issue. From buzzing to rattling, to hissing to grinding, each noise of an AC has a cause.

With the knowledge of what causes the noise of an aircon, you can ensure that your noisy aircon works quietly and effectively for a long time.

FAQs

1. Why is my AC making a buzzing noise?

Ans- A buzzing noise is generally produced if the electrical parts are loose or if there are any unwanted items in the outdoor unit or compressor problems.

2. Is it normal for an air conditioner to make some noise?

Ans-Yes, some humming sounds are normal when the AC is switched on.

3. Why is my indoor unit of the split AC making some noise?

Ans- It might happen for some reasons like loose panels, unclean filters, unbalanced fans, or unclean airflow.

4. Can an unclean filter cause an AC to produce unwanted sounds?

Ans- Yes, an unclean filter might cause the AC to produce unwanted sounds like whistling.

5. What do I do if my AC is making unwanted sounds?

Ans- You can call the technician if the AC makes unwanted sounds like banging, grinding, or hissing, or if the sounds do not go away after cleaning the unit.

6. How do I prevent my AC from becoming noisy?

Ans- You can prevent your air conditioner from making loud noises through regular servicing, cleaning of air filters, and cleaning of the outdoor unit.

7. What causes a noisy air conditioner even when it’s new?

Ans- A noisy air conditioner can occur due to improper installation, loose parts, or vibrations from uneven surfaces. Regular checks help prevent early sound issues.

8. What should I do if my AC is noisy only when cooling mode is on?

Ans- Check the fan speed, air filters, and airflow paths. Noisy ACs during cooling mode often indicate fan or motor issues or clogged filters.

9. Is it normal for a window AC making noise occasionally?

Ans- Window ACs can be slightly louder than split ACs due to compact internal components. However, excessive noise may indicate loose parts, debris, or motor issues.

10. How can I reduce a loud AC in my bedroom?

Ans- Make sure the AC is placed on a level surface, clean filters regularly, secure panels, and ensure there’s no obstruction in airflow. Using a ceiling fan along with the AC can also help.