Reasons Why Your Diffuser Is So Loud – And How To Fix It

More than a third of all Americans believe that essential oil diffusers have health benefits, and many people use them for aromatherapy or to create a calmer, pleasant-smelling environment. However, diffusers can produce a lot of noise while working and leave you wondering whether it is normal or if they should be quieter.

A diffuser can be loud because of low water level, mineral build-up, or fan-related problems. Other causes include a broken/defective diffuser or an uneven water reservoir. A diffuser can produce sputtering, crackling, grinding or rattling noises during operation, which indicate there is a problem with the unit.

This article will take you through all the possible reasons why your diffuser may be so loud, explain some of the common noises a diffuser may produce, and most importantly, provide step-by-step instructions on how to solve each problem.

Types of noises that a diffuser may produce

A diffuser can make several types of noises when in use:

  1. Sputtering- A sputtering diffuser produces gentle explosive noises that sound ‘liquidy’.
  2. Crackling- A crackling diffuser emits short, harsh noises in fast succession.
  3. Grinding-A grinding diffuser is one that produces a sound similar to one hard object colliding or scraping with another.

5 Reasons why a diffuser is excessively loud

There are various reasons why a diffuser may suddenly start making loud noises. This may be due to the device’s hygiene, poor maintenance, or because it is defective. Here are the five main reasons for a noisy diffuser:

1. Low water level

The fact that a diffuser is excessively loud is often the result of insufficient water in the reservoir. After a period of time (hours), when a diffuser becomes low on water, it typically begins to produce noise – usually a sputtering sound. Ultrasonic and heat diffusers are the most prone to this kind of problem.

When you notice your diffuser starting to make these disturbing noises abruptly while working, first confirm the water level. If its low and you intend to keep using the diffuser, be sure to refill it to continue enjoying the benefits of your favorite essential oils.

Luckily, many diffusers will automatically shut off and notify you when it runs out of water, so there is very low risk of the unit overheating.


  • Lack of misting.
  • Loud noises (usually sputtering).


  • When the diffuser is out of the water, refill it if you intend to continue using it.
  • To refill the diffuser, rinse once with clean water before filling it with water just slightly before the max line. Do not overfill it or use too little water in a diffuser. (Ideally use distilled water)

2. Scale or mineral build-up

Mineral build-up or scale can also cause a diffuser to make loud noises. This occurs when the diffuser becomes dirty or clogged with mineral deposits from hard water content. Naturally, over time, a diffuser becomes clogged with dirt or mineral build-up and requires cleaning.

If you notice your diffuser making more noise than usual and it still has enough water in it, check to see if it is clean by looking at the reservoir, and outlet in particular. A diffuser with dirt or mineral build-up will typically produce some sputtering or crackling noises when running because of reduced performance. Although, grinding and buzzing noises are also possible.

Extensive mineral deposits will make the diffuser struggle to disperse the essential oils and can also lead to the device overheating.

Scale, or mineral build-up, is most prevalent in ultrasonic, heat, and evaporative diffusers. Calcium and magnesium, which are present in all tap water but in higher proportions in hard water, are the two major ions responsible for mineral build-up.

To avoid scale formation in the reservoir or other elements of the diffuser, manufacturers define the type of water to be used in a diffuser in the user manual. You can avoid mineral build-up by using filtered, distilled, or demineralized water, which is devoid of the salts and metal ions that cause scale to deposit.

Water Purification Guide has a complete list of brands of distilled water available here.

Diagnosis for mineral build-up/scale in a diffuser.

  • Cloudy water of essential oils.
  • Greying or whitish hard substances in the reservoir.
  • Loud noises as the diffuser work.
  • Lack of misting.
  • Cloudy water tank as the diffuser works.
  • White dust around the diffuser.


  • Descale the diffuser (see instructions below).
  • Clean the diffuser regularly as directed by your user manual.
  • Schedule a regular cleaning routine.
  • Use water specified by the manufacturer (usually distilled or deionized).
  • Do not leave water sitting stagnant in a diffuser when it is not in use.

How to descale a diffuser.

  • Switch off the power and unplug the diffuser.
  • Carefully disassemble the diffuser.
  • Drain it of any remaining water.
  • Pour one liter of white vinegar into the diffuser’s reservoir and swish it for 5 minutes to ensure it reaches all parts of the diffuser, including the hard-to-reach areas.
  • Allow it to soak for at least one night.
  • Scrub it gently with a soft bristle brush for around 2 minutes in the morning before draining the vinegar solution away.
  • If any stubborn stains of mineral accumulation remain after draining the solution, soak a soft cloth in vinegar and clean the affected areas with the towel by scrubbing it gently and repeatedly until the scale dissolves completely.
  • Rinse the diffuser with clean water many times until it is sparkling clean and the vinegar odor is gone.
  • Wipe the diffuser’s exterior with a wet towel.
  • Allow time for it to dry before reusing it.

3. Fan-related issues

A diffuser can become loud because of fan-related problems. The fan in a diffuser propels the water mist out of the diffuser and throughout your home. Fan problems make a diffuser produce rattling, clicking, or grinding noises. It is particularly common with evaporative diffusers.

Problems related to fans include a loose fan, broken fan, or an obstructed fan. The job of a fan is to disseminate freshly generated essential oil mist into the air outside of the diffuser, allowing the device to diffuse the room effectively.

Usually, a diffuser is considered quiet when it produces between 0 and 60 dB, and anything above that is said to be loud. Fan-related problems can result in a diffuser producing noise well in excess of 60 dB.

If a diffuser is new and is loud due to fan-related issues, return it as it may still be under warranty. However, it is very rare for a new diffuser to have fan problems, and far more likely for a diffuser to experience fan issues over time and with regular use. Although, moving and/or dropping a diffuser can lead to a sudden loose or damaged fan.

When lubrication also dries up, the fan may become louder than normal due to dust build-up on and around the blades. You’ll usually be able to tell when this happens since the fan will become louder as the diffuser works.

Diagnosis for a fan-issue-related diffuser

  • Loud noise as it works.
  • Lack of misting.
  • Fan not moving easily when manually pushed (with the diffuser switched off and unplugged)


  • Contact customer care if your diffuser is still under warranty.
  • Lubricate fan bearings.
  • Replace the fan if damaged.
  • Buying a new diffuser if lubrication or fan replacement won’t help.

How to lubricate and change a diffuser fan.

  • Switch the power off and unplug your diffuser.
  • Drain its reservoir of any available water or essential oils.
  • Disassemble your diffuser’s parts one after another.
  • Keep all the disassembled parts safe as you will require them to reassemble.
  • Turn the diffuser upside down to locate the screws.
  • If you cant see the screws, access and locate any rubbers as some models’ screws can be hidden underneath.
  • After removing the rubbers, unscrew the screws one by one. You’ll need those screws later for reassembly, so keep them secure.
  • Pull the cover off cautiously after removing the screws to avoid injuring any of the cover’s beneath components.
  • There will be a lot of dust when you remove the cover.
  • Using a portable vacuum, clean the dust and grime that is easily accessible.
  • Be careful not to break or touch any parts while looking for the fan.
  • Before lubricating or replacing the diffuser’s fan, remove it from the diffuser.
  • Once you’ve located the fan connector, unplug it to allow room for easy removal.
  • Check the condition of the fan after removing it to see if it needs lubricating or replacement.
  • To lubricate it, partially peel the paper off the back of the fan, drop a single drop of oil into the hole where the axle and bearing are located, and then re-apply the partially peeled-off sticker.
  • After that, wipe the blades and fan cage using an empty squeeze bottle to remove any dust.
  • Remove the old fan’s connector, strip the insulation from both the fan and connector wires with wire strippers, slip a piece of heat shrink over each fan wire, and solder each set of red and black wires together to replace the fan.
  • After that, use adhesive to adhere the fan to the diffuser.
  • Replace the lid and use a screwdriver to tighten the screws.
  • Replace the rubber, rotate the diffuser, and reassemble it for the next time you use it.

Note: Keep in mind that doing troubleshooting or opening up a diffuser that is still under warranty, whether by yourself or by a specialist, will typically void your warranty.

4. The diffuser is faulty or broken

It is also possible that a diffuser is loud simply because it is faulty or broken. No matter the type of the diffuser you own, it will break if dropped or bumped. Any buzzing or grinding noises that you might be hearing could be an indication the diffuser is broken.

Because there are so many reasons a diffuser could be loud, access the diffuser carefully to examine what the problem could be. If it is broken, you will know when you carefully examine the diffuser because the signs of a broken diffuser are obvious; a crack, hole, or leakage etc.

Diagnosis for a broken diffuser

  • Loud noises.
  • A visible crack.
  • The diffuser is leaking.


  • Call your manufacturer if the diffuser is still under warranty.
  • Replace the broken part.
  • Consider buying a new diffuser.

5. Unstable water reservoir

An unstable water reservoir could also be why a diffuser is making loud noises. Diffusers have reservoirs that need to be filled with water and essential oils. When a diffuser’s reservoir is filled with water and essential oils and placed on an unstable surface, it can start producing loud noises as it works.

This is especially normal with ultrasonic and heat diffusers. When a diffuser’s water reservoir is not stable or correctly positioned on the base it can cause the entire ultrasonic diffuser to vibrate. The water tank itself can also rattle each time the diffuser operates, making an increasingly annoying noise.


  • Press down or hold the water tank with your hands while the diffuser is on; if the diffuser becomes quieter, the problem is most likely an unstable water reservoir.
  • Diffuser overflowing with water.
  • If your diffuser has a cap/lid, check that it is properly fastened.


  • Switch the power off and unplug your diffuser.
  • Take the water tank out of the bottom of the device.
  • Double-check for dirt, debris, or moving parts in the water tank and its slot. Remove any that you find.
  • Check for anything trapped on the outside of the water tank as well.
  • Get rid of any that you find.
  • After that, gently replace the water tank in its slot. There is usually a clicking sound when it fits perfectly.
  • If the water tank appears to be fractured or cracked, you should consider replacing it.
  • Always refer to your user manual for any troubleshooting instructions.

Can I make my diffuser quieter?

A diffuser can be made quieter by being positioned it on a flat, hard surface, and away from any walls, cleaning it regularly, and using the right amount of water in it. Other ways to make a diffuser quieter include avoiding using hard water in it and creating a regular maintenance routine.

Theresa Orr

Theresa Orr holds a PhD in Earth Science and specializes in determining past climates from rocks using geochemistry. Her passion for clean water, soil and air drives her to provide easy to understand information for everyone to read.

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