Why Air conditioner makes a loud noise when starting? (causes & Fix)

The AC (Air Conditioning) system significantly contributes to your house’s noise level. You may have noticed that your room is freezing and your AC unit rattles and vibrates when you turn it on. There are many reasons why this happens, including:

An air conditioner is a device that cools off your home by recirculating outside air. The system works by moving refrigerant from a heat exchanger to an evaporator and back to the room. When something disturbs the air conditioning system, this can cause some noise to be heard.

The sudden but unmistakable sound of an air conditioner could signal that something is wrong with the air conditioner.

In this article, we’re going to discuss how to prevent loud, surprising noises from damaging your home. We’ll be examining five warning signs that should immediately alert you that noise is coming from the outside world.


Various types of AC Noises Causes and Fix:

A faulty outdoor fan, ballast, or blower is a common problem. This article will discuss some of the most commonly encountered problems and tell you what to do if you find yourself in these situations.


1. Humming or buzzing noise:

Humming or buzzing noises are often signs of electrical problems and should be considered. The humming noise is caused by the motor spinning up to create a sound. The engines can also be damaged when the compressor overheats and starts humming.

Humming is a common problem in both AC units and air conditioners. The hum is caused because of debris trapped inside the unit.

Buzzing noise from your air conditioner is caused by: · Loose parts · debris in the outdoor or indoor unit. The most common type of noise you will hear is caused by the: · Outdoor fan motor. To fix a buzzing noise in an outdoor unit, ensure that no debris obstructs the blades and then make sure to · Check for loose parts.


Causes: Debris in the outdoor unit or indoor unit, Loose parts of any Ac unit

Fix: The condenser coil needs to be cleaned. The copper lines from outside to inside have rubbed against the condenser coil. The condenser coil needs to be cleaned. The air filter needs to be changed. The blower is out of balance or not working well enough.





2. Banging Noise:

Banging is a familiar noise in air conditioning and refrigeration systems. It’s a symptom of mechanical problems caused by loose or broken parts. This can make it difficult or impossible to maintain the cooling process, potentially affecting the customer’s comfort and performance.

You’ll have to clean the fan if you have an old unit with a loud knocking sound coming from it. The fan might be generating lots of Banging noise because of the old age of the ac unit, and there are chances that it’s blocking airflow in some places. You can also notice a dropped blower motor when the compressor is running, so it’s time to fix the blower problem to eliminate this sound.

Cause: loose or broken parts of Air conditioner unit and dropped blower motor.

Fix: Remove the blockage or tighten problem parts. Fix the blower problem.

3. Clanking Noise:

AC Clanking Noise is one of the most familiar types of noise generated by electronic devices. Clanking is a sign of a loose or out-of-balance part. Clanking noise can be caused by friction or leakage over time and is less noticeable in cold climates.

Indoor blower and outdoor fan, if not balanced properly, can cause internal pressure to increase and cause damage to the motors, and can create a clanking sound. The blades may be damaged, and they can even break. If the blower motor is out of balance, it will only generate turbulence and force air to move sideways. This makes it harder for airflow to move into the room and creates more noise.

Cause: It usually comes from defective or loose parts, leaking capacitors, or overheating.

Fix: Check for any debris around the fan blades to prevent banging and clanging noises from your machine upon startup.


4. Screeching Noise:

If you have a screeching noise in your audio equipment, or a whirring noise coming from your cooling fans, it might indicate that your fan motor bearings are failing. For example, if the blades of your cooling fans begin to move at high speed and make a loud noise, it could indicate that the bearings are worn.

The screeching sound may not be music to your ears – but Screeching sounds are annoying. They can be created from the duct system of blower fan motors. Outdoor fan motors may also loudly squeak when they’re going bad. Blower fans and engines may be noisy, but they don’t need to be repaired or replaced.

Causes: The fan motor bearings are failing or have been irreversibly damaged.

Fix Replacement or repair of the cooling fan motor.


5. Squealing Noise:

AC Squealing Noise is a result of mechanical vibration that occur for proper cooling. A noisy blower or blower motor can be the source of ACS.N., especially when mounted near an outside wall.

For some units, this sound is typical upon startup. You should be able to identify whether it’s a sound that the air conditioner unit always makes or if it’s something new. For squealing sound, consider the fan blades of your air conditioner unit. If you have a brand-new ac unit and cannot find the fan blades even after looking for a day, it would be a good idea to look for debris around them.


Causes: AC Squealing Noise (ACSN.) is a form of noise caused by mechanical vibration due to a lack of proper cooling.

Fix: Check the cooling fan. If it has any problem, you can repair it.

6. Clicking Noise:

Clicking electrical components at startup or shutdown is a natural part of the system’s operation. But if the clicking happens constantly or irregularly, it could be a sign of a defective control or an equipment problem. We will discuss this issue in detail.

The power cut causes the clicking noise, which may be heard in different parts of the building. It may be noise.


Cause: The thermostat, compressor, or capacitor might be faulty inside the Ac units, or any electrical faults can occur.

Fix: Repair those thermostats, compressors, or capacitors or Call any HVAC specialist.


7. Rattling or chattering Noise:

A rattling sound is one of the most common signs of a malfunctioning AC It can mean that your air conditioner is starting to deteriorate, and some of its parts are loosening. Another cause could be twigs or leaves that have clogged your system. It would usually signify impending trouble because you can easily maintain such a system by changing the filter, replacing the coolant, and changing any other elements that might have clogged the system.

The compressor has a high-power requirement and is located near the electric motor. If a chattering sound generated by the engine is produced, it will damage other components. The brakes are energized to stop the machine immediately.

Causes: It can be caused by several things, including loose electrical wires, damaged parts, or even an old broken unit.

Fix: Tightening loose wires, Repairing damaged parts, fixing broken units.

8. Pulsating Noise:

A pulsating noise results from the air conditioner’s compressor motor spinning at high speed. Sometimes, the noise is so loud it can be heard up to a mile away!

Many people don’t realize that an air conditioner can create a pulsating noise. This type of noise is caused by the rotating motion of the compressor, fan, or other parts of an AC unit. This sound is most commonly heard when the unit works and works hard.

If your outdoor A/C unit is making pulsating noises, don’t panic. This is a normal condition, and it can be resolved quickly. If the problem persists for more than 24 hours, you should contact an electrician to repair or replace the unit.

Causes: Fan systems can become noisy and also be prone to breakdown, so it is a good idea to replace the blower motor periodically.

Fix: Newer motors with less fan noise significantly improve over older ones.

9. Whirring Noise:

One of the most common complaints amongst homeowners is that their outdoor A/C units are making a Whirring noise. You can’t hear it from inside the house, but it’s there when you open the patio doors and windows.

It isn’t easy to diagnose the cause of a Whirring sound at your Air Conditioner. It can be challenging to identify the noise source; therefore, you must take measures to avoid any interruption or damage done to your AC unit.

Cause: Whirring sounds result from many things, including dirty air filters, dusty air filters, overheated outdoor blowers, or indoor electric fans.

Fix: Cleaning the filters, in turn, can solve the whirring sound problem.


Common causes Air conditioner makes a loud noise when starting:

air conditioner makes a loud noise when startingThe dampers are a significant component of every air conditioning system. If they fail, you’ll notice a sudden loud noise. It may not be that loud, but the picture is clear: Your air conditioner has failed, and it’s time for a repair.

As temperatures rise, the expansion and contraction of ducts is a common cause of problematic creaking noises.

The compressor motor in a refrigerator, air conditioner, or AC unit is usually the noise source. However, it is not always the culprit. Many areas of the electricity grid in our homes and offices are constantly producing energy that we don’t need! When this happens, the power we don’t use is sent to waste.

There could also be a problem with the fan or air handler that’s causing the blower wheel to bang against another part of the unit. In some cases, the fan’s mounts can get loose and throw it off balance as it slows down, causing it to hit its enclosure.


The dampeners are installed in the ventilation system to control airflow and prevent loud noises from escaping. The slamming noise is caused by the air being pushed up but unable to get out the vent.

You need to reduce the noise of your air conditioning system by changing the settings. You can choose to install a damper or use an accordion-type device mounted on the ceiling ducts.

Fan noise is a significant problem for air conditioners. It could cause damage to your unit and even lead to overheating and damage. To avoid this problem, you should turn off the fan when not in use.



When to Replace a Noisy Air Conditioner?

Something may be wrong if you have an air conditioner that suddenly makes an unusual noise. It is worth checking out the details of the problem before calling a service professional. Here are some tips to help you check out your air conditioner before you call for assistance.


If you have a noisy air conditioner, the most common solution to this problem is to replace it. However, replacing an AC unit may not.

When replacing a noisy air conditioner, it is essential to check the unit’s age and replace it when necessary. A noisy air conditioner is usually a sign that you have an older ac unit and should be replaced if you are

When you purchased your new air conditioner, it probably was higher than the previous one and made lots of noise. You will need to buy a new ac unit to keep your home cool. When you buy an air conditioner, the price can be very high; but if you can sell it for the same price as an old model and get the savings in electricity bills that this old one.

A new air conditioner will be much quieter and more efficient, too. Your old air conditioner has a significant carbon footprint, so you may even have more energy in your electricity bill than you paid for the old one.


The noise level is not a problem when it’s working properly. But if you suspect the unit is not operating correctly, you should examine the ac unit to make sure there are no loose parts, debris, or loose fan blades. To check if the outside air conditioner unit is working correctly, open the door and look at the outdoor airflow. If there is no airflow, then you should replace your ac.

The cooling system of the air conditioning unit is the most critical component of a refrigeration unit. It should be checked regularly to ensure it operates efficiently and keeps the system from overheating.

It is time to address the problem. Our air conditioner or refrigerator is not cooling as it should. It was most likely the compressor that broke down at some point. It may have been caused by leakage of a condenser coil, air filter, blower motor, etc.



Leave a Comment