Air Conditioner Makes Loud Noise When Starting

image of homeowner covering ears due to loud air conditioner noises

A machine that makes some degree of sound while operating is not a surprise. After all, refrigerators, dishwashers, and washing machines aren’t a hundred percent quiet. Air conditioners also produce a faint sound. However, a loud noise coming out of your unit is not normal. For instance, you may hear your air conditioner makes loud noise when starting. It is prudent that you investigate the reason behind any noise that’s out of the ordinary. It may be a symptom of a bigger issue with your air conditioner. Read on to learn several causes and solutions for a loud air conditioning unit.

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Air Conditioner Makes Loud Noise When Starting

Homeowners frequently hear loud noises from an air conditioner when it starts up. Various kinds of noises can be heard, so listen closely. Each type of noise indicates a unique problem that needs to be resolved. Remember to always contact a reliable HVAC technician to assist you instead of fixing it on your own.

Types Of Air Conditioner Noises & Their Causes

Here are some of the strange air conditioner noises you may hear:

Clanging & Banging Coming From Air Conditioning Unit

air conditioner condenser fan close up

The outdoor unit of an air conditioner has a blower that moves air to the indoor space. A damaged blower motor can result in odd noises. Components may become loose and start hitting the cage. Other likely suspects are fallen debris, damper movement, and thermal expansion.

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Screeching Air Conditioner

air conditioner condenser fan close up

If you hear something like metal grinding against metal, it can be because of broken fan motor bearings. It is not an emergency, but it is best not to let it get worse. Hire a competent HVAC professional to repair it before turning on your air conditioner.

Clicking Air Conditioner

Electrical issues can cause clicking sounds. You may try starting your air conditioner, but it may never turn on. This problem should be resolved by professional HVAC technicians who can focus on checking the thermostat, compressor, and capacitor.

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Pulsating Cooling System

It is expected that you will hear a low-level pulsating sound as air flows throughout the system. This noise from the outdoor unit shouldn’t be heard inside your home. If you hear them indoors, you may have a problems such as a broken fan blades or twigs inside the unit.

Whirring Air Conditioner

image of an hvac contractor performing air conditioner tune-up

Mechanical problems in the air conditioner can generate a whirring noise. The indoor and outdoor units can emit this sound. Common reasons include blown fan motors, broken belts, faulty blades, and bad bearings. Call a technician for repairs after immediately switching off your air conditioner.

Buzzing or Humming Coming From Air Conditioner

Check for debris inside the outdoor air conditioning unit if it has an audible hum. Branches, flowers, and leaves may have slipped through the holes. Remove them immediately. The fan may also be going bad if you hear a buzzing sound.

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Rattling Air Conditioner

Loose air conditioner parts may cause rattling. These components may have become loose over time because of the vibration. They may need to be tightened. It is also best to have the coils cleaned, and the filters changed after. Better yet, contact a reputable HVAC contractor to conduct yearly AC maintenance.


Common HVAC Contractor Fixes for Loud Air Conditioning Units

Read on to learn more about how these air conditioning noises can be repaired.

Clean & Straighten Coil Fins

The coil fins should be kept clean for enhanced performance and efficiency. Contact an HVAC contractor for annual air conditioner maintenance. They can help straighten the coil fins with a fin comb while using a vacuum with a brush extension to get rid of the dirt around the area.

Tighten Loose Screws

The air conditioner vibrates while running because it has many moving parts. This is entirely normal. However, this vibration can loosen the screws after some time. It can eventually cause a rattling sound that is heard whenever the cooling unit is on. Routine HVAC tune-up should have tightening of all screws as part of its tasks.

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Remove Debris in the Blades

The HVAC contractor may open the air conditioner cabinet to see inside. They will remove any debris right away, especially any foreign objects around the fan blades. This should be a quick and easy task.

Straighten Bent Blades

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Check the blades for any issues after removing all dirt and debris. An HVAC contractor can bend any uneven blades back into shape. They can do this task carefully so that the problem doesn’t worsen. Each blade will be checked until everything is in order.

Lubricate Motor

Screeching sounds can be because of poor motor lubrication. Tune-up services usually include lubricating the motor, so this problem doesn’t occur in the first place. HVAC professionals will use proper oil to eliminate the noise. They will also add oil to the oil ports close to the bottom of the fan motor.

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What A Homeowner Can Do If The Air Conditioner Produces A Loud Noise

Read on to explore how homeowners can address these unusual air conditioning noises.

Check the Outdoor Fan & Inspect the Unit

Check the condenser fan, located in the outdoor AC unit. If it rotates, see how the blades spin. Debris can cause it to become off-balanced or suddenly make contact with other components. Check the refrigerant piping and coils as well. Skip this step if you do not know what you are looking at. Leave it to a professional instead.

Change Your HVAC Air Filters

image of a dirty air conditioner filter that needs replacement

It is essential that all homeowners do this task. An air conditioner cannot operate well if it has clogged filters as the airflow will suffer. This will result in the unit struggling and emitting a humming noise. Check the air filters at least once a month and replace them as needed.

Clean Your Outdoor Air Conditioning Unit

The outdoor unit is exposed to the elements. It can result in dirt and debris getting inside the unit via the slits. Turn off the unit before opening the case to ensure your safety. Remove the top grille and take any fallen objects. Remember to close it again once you are done.

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Check the Run Capacitor

Turn on the air conditioner after cleaning it. See if the fan is spinning this time. If it doesn’t, try jump-starting it by pushing the blades with a long stick. This should create momentum. You likely have a malfunctioning run capacitor if the blades start spinning.

Inspect Your Indoor Air Handler

The problem may not lie with the outdoor unit at times. Once you have checked it thoroughly, inspect the indoor air handler next. There could be bent coil fins or ice accumulation. Switch off the power to defrost it. Make sure it is dry before switching it on again.

Call an HVAC Company

Homeowners can do many tasks to avoid air conditioner problems. However, untrained individuals are limited. If you still hear odd noises from your air conditioner after checking for deris and replacing the air filter, it is time to ask an HVAC technician for professional assistance.


Preventive Measures for Air Conditioner Starting Problems

Here are preventative steps you can take for AC starting problems:

  • Install Noise-Reducing Barrier: Noises from your air conditioner can make it hard to focus on your day-to-day tasks. It can also keep you from sleeping soundly at night. Install a barrier to minimize the noise. A noise-reducing fence or a sound blanket is ideal for this purpose. Consult a reliable HVAC technician to help you.
  • Schedule Regular HVAC Maintenance: Book air conditioner maintenance at least once a year. Professional HVAC technicians have the trained eyes to find the problems your unit may have at its earliest stages. They can repair these issues with immediate solutions so they do not worsen. The techs will thoroughly clean the unit, so you won’t have to do it yourself. This lowers the likelihood of loud noises developing in your air conditioner.
  • Call in an HVAC Expert: Contact an HVAC technician as soon as you hear unusual noises from your unit. Do not ignore them so that they don’t get worse. It is always more affordable to repair minor AC problems than to remedy full-blown failures.
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Give close attention to your air conditioner. It will alert you if something is wrong. Manufacturers have worked hard to minimize the noise of air conditioners. After observing your air conditioner for some time, you can get a feel for what is normal. Investigate your unit immediately if you notice something is wrong. Ask help from a dependable HVAC technician for advanced repairs.

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R.F. Ohl provides top-notch HVAC services in the Poconos and the Lehigh Valley, Pennsylvania. We have only the best professionally certified and highly skilled technicians for all your heating and cooling service needs, including boiler replacements, furnace repairs, air conditioner maintenance, and much more. All our skilled techs have the knowledge and experience to service your HVAC system promptly and correctly.

Rest assured, our company has one of the most affordable HVAC service rates in the locality. Our tune-up services can assist in increasing your energy efficiency and home comfort while reducing energy costs. If you need to replace or repair your HVAC system, we can recommend the best solutions within your budget. All our work is guaranteed. Call R.F. Ohl today to book a service appointment. We offer free, in-home estimates.

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