How to Clean Your Essential Oil Diffuser | Troubleshooting Tips

Last Updated on November 11, 2022 by Brenda

How to clean a essential oil diffuser

You’ve been using your essential oil diffusers for a while now and they need deep cleaning that doesn’t take much time to do but needs to be done from time to time for the best efficiency dispersing the mist into the air. Bacteria and microbes lurk inside the unit and you want to breathe in the clean mist with your essential oils. Mold spores can grow in water. Use the methods below for cleaning to keep your diffuser in top-notch condition removing all the residue. To keep your diffuser clean and ensure the best from your essential oils, follow the steps below for how to clean diffusers.

Troubleshooting tips are listed at the bottom for fixing problems you might encounter with your diffuser.

Two Major Types of Essential Oil Diffusers


Ultrasonic diffuser

These units are akin to nebulizer diffusers except these use water to which you add your 100% pure essential oils on top of the water in the reservoir. Ultrasonics are more powerful than nebulizers but nebulizers use no water, so the mist aroma is more intense.

Ultrasonic diffusers using water produce a small amount of humidity that’s good to have during the winter and summer’s dry days. These diffusers cost less than nebulizers. Both types create a cool-mist since no heaters are built into the unit. These diffusers have larger water tanks to hold water. Most have many LED lights to set a mood or for youngsters to enjoy.


Nebulizer diffuser

The nebulizer uses 100% pure essential oils for a more intense fragrance and are ranked higher for their therapeutic quality using only pure oils. The oils are used right from the bottle for a substantial amount of oil dispersed into your environment.

These are more expensive, need more refilling, but are worth it for the benefits. Many of the units have timers where you can conserve oil by running the mist at intermittent intervals. Many of the new nebulizers use glass tops for the oils with LED lights showing in the glass top. They are elegant and functional. Clean the glass the same way as an ultrasonic diffuser.

How to Clean Your Essential Oil Diffuser

Essential oil diffusers are available in different shapes and colors made of glass, wood, ceramic, aluminum, and plastic with many diverse functions.

It’s frustrating when diffusers start acting strange. Most of the time, it simply needs a good cleaning to be at its best again. Learn how to clean diffusers for essential oils quickly.

Check your User’s Manual since all diffusers can vary in the cleaning process before you start cleaning. It’s not rocket science to clean aromatherapy diffusers.

How to deep clean your diffusers

6 Simple Steps To Clean Your Diffuser

Unplug your cable from the diffuser1. Unplug your cable from the diffuser so you will not be shocked. Water and electricity do not go together! Be safe, not electrocuted! It’s a good idea to unplug the power cord from the wall outlet as well.
Empty out any existing oil and water
2. Empty out any existing oil and/or water. Fill the diffuser half full of water but never over the max line.
The vinegar
3. To remove the residual oils from the diffuser’s glass or plastic, add up to 10 drops of clear distilled vinegar and let the diffuser run for 5- to 10-minutes. The vinegar will go through the tubes that send out the mist to clean the oils off as well. It doesn’t matter what brand you use as long as it’s not the dark apple cider vinegar.

4. Drain out the vinegar and water. If you do not want the vinegar smell lingering, fill it to the max line with water and run another 10-minutes to rinse well.
5. Use a cotton swab to thoroughly clean corners and nooks to remove any remaining oil stuck on. If your diffuser has a round sensor disc with a retaining ring in the middle bottom of an ultrasonic diffuser, clean it gently with a cotton swab and not the brush that can come with the unit. Never immerse the diffuser in water and never soak any top in liquids.
cotton cloth
6. Air dry or use a cotton cloth, not paper towels that break off and stick to parts. I have used a hair blow dryer that works quite well but not too close to the diffuser.

Optional methods: Fill the water reservoir up to the Max line with water and one tablespoon of citric acid (sour salt). Use a cotton swab to clean after letting the mixture soak 5 to 10 minutes.

Pour out the solution being careful not to let it get into the air outlet hole on the side. Never submerge the unit in water. Allow the unit to air dry or use a towel to dry it inside and out. Mildew and bacteria will grow in your diffuser if you let water sit inside for days and weeks and feel slimy. Always leave it clean and dry when not in use.

Use alcohol on a cotton swab and clean or use dish detergent with water on a cotton swab. Dish detergent will suds up and be hard to rinse if you put it in your diffuser to run it through. You can let alcohol sit in the base all night.

Be sure your Owner’s Manual says it’s okay to use vinegar. Some manufacturers will void the Warranty if you use vinegar. You can always call customer service at your manufacturer’s website. Always clean your diffuser according to the instructions in the User’s Manual.

It’s best to dump out the water/oil content daily since tomorrow might not be the day you use it again and it could be a week with mold growing on top. Oils are volatile and corrosive and letting them sit in your diffuser can ruin the diffuser inside. Additionally, the aroma will influence the smell of another oil flavor you add to it. You can quickly dump it and dry it out doing a complete cleaning another day.

Troubleshooting Tips

Diffusers don’t have that many parts inside; however, occasionally they will burp, and you think it’s done for. Most problems can be fixed using the tips listed here. Sometimes if you need a part, it’s cheaper to buy a new diffuser.

Diffuser Has no Power

  • Be sure the power plug is tightly plugged into the wall outlet or USB port if you have that type unit.
  • Check to see that the connector to the diffuser is plugged in tightly.
  • Be sure you are using the power adapter that came with the unit.
  • Be sure the water reservoir is full of water to the max line for an ultrasonic diffuser and over half full in the bottle for a nebulizer diffuser.
  • If you’ve just cleaned it, make sure it’s super dry.

Small Amount of Mist

  • Make sure the water in an ultrasonic or oil level in a nebulizer is where it’s supposed to be.
  • The fan inlet hole for air must be clean and not blocked. Clean your unit if it has dried oil or dirt in it.
  • Did you turn the mist level too low?

Water Level Is High and Hot in the Diffuser

  • Ultrasonic diffusers do not use heating elements to heat the water! They are cool-mist diffusers.
  • If the water feels hot, you have too much water in the reservoir and should remove it to the max line.
  • Turn the diffuser off, unplug at the wall and at the diffuser base.
  • Dump out the water contents and save it if you have oils in it.
  • Let the diffuser cool for an hour or so.
  • Refill with the water and oil you saved to the max line only.
  • Turn it on. If it doesn’t start or is still hot, you have damaged your diffuser by overfilling and will need to have it repaired.

Water Level Is Normal and Hot in the Diffuser

  • The air intake for the fan to turn might be blocked with dried oil or dust.
  • If your diffuser sits on a towel or mat, remove it.
  • Disconnect the plug at the wall and base of the diffuser.
  • Open the diffuser by removing the screws to see if dirt, hair, or dust is stuck on the fan blades then remove. Put the diffuser back together.
  • Remove any water with oil and save it for later.
  • Let the diffuser cool for an hour or so.
  • Refill with the water and oil you saved to the max line only.
  • Turn it on. If it doesn’t start or is still hot, you have damaged your diffuser and will need to have it repaired.

Lights Flash on Switches but Diffuser Won’t Start

  • Sensors do malfunction, even in diffusers.
  • Disconnect the plug at the wall and base of the diffuser.
  • Remove any water with oil and save it for later.
  • Let the diffuser cool for an hour or so.
  • Refill with the water and oil you saved to the max line only.
  • Turn it on. If it doesn’t start it might be damaged diffuser and you will need to have it repaired.
  • Sometimes the switches get out of sync. Try different switches and see if it works.
  • If you’ve gotten water into a switch, let it dry for a few days and try again.

Diffuser is Loud

  • Depending on the motor or fan strength of your diffuser, some noise is normal during operation. If the unit is making a noise that sounds abnormal don’t use it and call the manufacturer’s customer service people.

You can visit diffuser doctor to browse and see what you need to fix your diffuser. Some items at this site are very inexpensive and might be just what you need.

Avoid Thick Oils

Avoid Thick Oils

Almost all essential oils are thin like water. Viscosity means thick, such as car motor oil. Some diffusers will not work with Valor, Vetiver, Patchouli, Sandalwood, or Myrrh and cause clogging. Lavender and Peppermint are good examples of the right viscosity.

Tip: To protect the bottle’s label, put the bottle of thick oil into a small plastic bag pushing out all the air so it won’t float. Seal the bag tightly so no water gets in. Put the plastic bag into a bowl or cup of hot water from the sink faucet. Remove the bottle after a few minutes; you can see the oil moving inside the bottle. It should now pour out of the bottle with no problem. It will thicken again, so do this the next time too. Being naturally thicker, these oils will not drop as fast as thinner oils.

Final Thoughts

Now you have the ways for how to clean diffusers that will keep them up and running for many years. Diffusers are a financial investment and with the proper cleaning they will operate quietly and perform without any problems.


Welcome to my blog! I am Brenda Star and I am a true believer that Nature is fascinating and enchanting. The history of herbs and their uses are captivating. I have always wondered how did the ancient people know—how did they come to understand what a plant would do. They did not experiment in a lab because those technologies did not exist. That wisdom will always be a mystery to me. More about me...