How to Fix a Loud Humidifier

How to fix a humidifier that makes a loud noise

Many people benefit from using a humidifier to increase moisture levels in the air. But while humidifiers are practical devices, it is also practically inevitable that they wear out over time and become louder.

The most common causes of a noisy humidifier or vaporizer are issues with the internal fan or with mineral build-up in the base of the device. In this article I will show you how to fix both of these problems yourself.

Let’s see if we can prevent you from having to buy a new one!

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This article was written with portable humidifiers in mind, and not the whole-house type. There is overlap between these two types, however, so it is possible that you can use some of this information for whole-house humidifiers as well.

Why do humidifiers get louder over time?

There are various reasons why a humidifier can get noisy over time. They range from lack of proper cleaning to components that start to fail. Sometimes it is easy to fix, whereas other times it needs a bit more work.

In my experience, the most common causes for loud humidifier noises are the following:

  • Mineral build-up on the ultrasonic transducer
  • The internal fan has started to wear out
  • A damaged fan
  • Other physical damage to the device

Mineral build-up on the ultrasonic transducer

The transducer in a humidifier is responsible for creating cold mist. It works by vibrating at a very high (ultrasonic) frequency. When water comes into contact with it, the water turns from a liquid into a vapor.

Top view of the base of a humidifier with its transducer and heating element visible.
The transducer is the black with white component in the center.

Over time, minerals from the water stay behind and build up on the transducer. When enough minerals have built up, the transducer is not able to oscillate properly anymore.

You can tell this happens when less or no mist comes out of the humidifier anymore, or, in severe cases, when the humidifier makes a grinding or buzzing noise. The latter can also occur due to problems with the fan, however.

Mineral buildup is the main reason for regularly cleaning the base of a humidifier. This is also why it is recommended to fill the device with distilled (a.k.a. demineralized) water instead of tap water.

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Not all humidifying devices use an ultrasonic transducer. Some use a heating element that turns water into hot steam instead. The heating element must be regularly cleaned too. That way it keeps conducting heat well.

The internal fan has started to wear out

Another common cause of a loud humidifier is the internal fan wearing out. In ideal circumstances, it takes a couple of years of use before you see this. But if you use a humidifier in a dusty environment, you can see it after a year of use or even less.

The fan is responsible for blowing freshly generated mist into the air outside of the humidifier. At the same time, it supplies the device with fresh air to humidify.

You can tell that the fan has started to wear out when the humidifier has gradually become louder.

The internal fan is at its most silent when it is clean and properly lubricated. Dust that reaches the axle and bearing of the fan can cause the lubrication to dry out, however. As a result the fan wears out more quickly and gets louder.

Dust can also build up unevenly on the blades of the fan, causing the blades to become imbalanced and create additional wear.

If you catch this in time, it is often enough to simply clean and lubricate the fan.

A damaged fan

There are times when the fan is simply too far gone and you can not fix it by lubricating it anymore. At that point, it will have developed some physical defect along with a clicking, rattling or grinding noise.

The only solution for this is to replace the fan. This might sound daunting, but it is easily doable with the right tools and it saves you from having to buy a new humidifier.

Other physical damage to the device

In some cases, there might be a different cause of humidifier noise. For example, when the device was dropped and it sustained damage when it hit the ground.

This is unlikely, however, for two main reasons:

  1. Damage from dropping the device is more likely to show up as cracks and leaks in the tank than damage to the internal components.
  2. In most humidifiers, the transducer and fan are the only moving components. Static components are not responsible for loud or weird noises you hear in a humidifier.

You can find the fixes for the above issues in the guide further down the page.

Can this guide be used to fix loud noises in all humidifiers?

While I fixed a Levoit LV550HH humidifier in the images below, the steps should translate quite well to other portable humidifiers. No matter if they work with cool mist, warm mist or steam.

I don’t have much experience with whole-house humidifiers, but because they work on similar principles (steam + fan), cleaning the unit and lubricating the fan should improve their sound levels as well.

What about vaporizers?

The repair guide below works for vaporizers too. Vaporizers generate mist by heating water instead of using ultrasonic energy. As long as the device has a fan that has gotten louder, it can be fixed with the steps below.

How to fix a noisy humidifier

In my experience, the best way to solve problems with a noisy humidifier is to first thoroughly clean it. The next step is to either lubricate or replace the fan, depending on what state it is in.

The more worn down and noisy the fan is, the more likely I am to just replace it. This helps avoid more issues with the humidifier later on.

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When humidifier problems, be sure to check the manual for any relevant information.

Cleaning a humidifier itself

Cleaning reduces the most sound in humidifiers that create cold mist. These use an ultrasonic transducer that gets hampered by mineral buildup.

When enough minerals collect on the transducer, the humidifier will start producing less mist. In severe cases, you will also start hearing a grinding sound.

That said, it is still a good idea to properly clean warm-mist humidifiers once in a while.

Here is how you clean both types of humidifiers:

  1. Turn the device off and unplug it.
  2. Remove the water tank.
  3. Remove any water from the base of the device, following to the instructions in the manual.
  4. Pour a layer of undiluted white vinegar in the base of the humidifier.
  5. Wait at least 15 minutes to let things soak.
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Don’t run the humidifier while it contains vinegar!
  1. Use a cotton swab to remove any mineral deposits. You will encounter these on the transducer and/or heating element and on the plastic of the base itself.
  2. Empty and rinse the base.

After cleaning, you might have to run the humidifier with water for a while before the vinegar smell completely disappears.

Fixing a loud humidifier fan

The section below contains the steps for both lubricating and replacing the fan. There is a lot of overlap between these two fixes, so the first couple of steps you see will be for both methods.

Cleaning and lubricating the fan should be done when the sound of the humidifier has not gotten that bad yet. It gives results for a limited amount of time. From a couple of weeks to a couple of months.

Replacing the fan is best when the fan has already gotten fairly loud, or if it has started to make a rattling, buzzing or otherwise annoying sound. In combination with clearning, this will give you the same lifetime out of the device as you originally had.

What you’ll need for cleaning and lubricating the fan

What you’ll need for replacing the fan

Part icon Parts
560PCS Heat Shrink Tubing 2:1, Eventronic Electrical Wire Cable Wrap...
13,227 Reviews
Replacement Fan
The specific type/model you can only find out after opening the humidifier. Instructions on how to do this and the best places to buy a replacement humidifier fan are listed below.
x 1

Opening the device

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Before doing anything else, first unplug the device and remove all water.
A hand lifting the reservoir tank out of a humidifier.
If you haven’t done it already, take the reservoir and put it aside. You can skip this step if the humidifier does not have a detachable reservoir.
The underside of a flipped over humidifier.
Flip the humidifier over so that you have access to the underside. This is where we find the screws that let us open the device.
A screwdriver being used to pop out a rubber foot from the underside of an electronic device.
If you don’t see any accessible screws on the bottom, remove the rubber feet. Screws are often hidden under here. The rubber feet can be popped out with a screwdriver. They are usually attached with a bit of adhesive.
Close-up of a plastic device housing with the exposure locally increased to show a screw.
Look into the screw hole with a light to see what type of screw head is used. This tells you what screwdriver bit you need to use. Alternatively, you can make a picture and increase the exposure around the screw, like I did here.
A screwdriver being used to remove a screw to fix a humidifier.
Use your screwdriver to remove all screws.
A close-up of three Phillips-head screws and one tricky tamper proof screw.
Tricky! This humidifier uses 3 regular Phillips-head screws and one tamper proof screw with a triangular drive. Situations like these are why it is useful to have a repair toolkit with a variety of bits.
A hand removing the panel from the underside of a humidifier that is being repaired.
Remove the bottom panel. If you have removed all screws, it should come right off.
The inside of a humidifier with a lot of collected dust.
Dust everywhere. You can expect to see a lot of dust if that is what has caused the fan to wear out prematurely.
A close-up of a switched-mode power supply capacitor covered in dust.
Now that the device is open, pay attention to not touch any capacitors or other exposed components on the circuit board. Capacitors can contain a potentially dangerous charge that you do not want to come in contact with.
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Recommended reading: How to Safely Discharge Capacitors
A vacuum hose being used to suck up loose dust that has collected in an electronic device.
Before moving on to the next step, it is a good idea to use a vacuum to remove any dust from the humidifier. We do not want this dust to end up in the fan again when we are done.

Detaching the fan

Regardless of whether you want to lubricate or replace the fan, it needs to be taken out of the humidifier for easy access.

A blower fan inside the electronics compartment of a loud humidifier.
Identify the fan. It is nearly always a blower style fan that looks like this.
A hand unplugging a red connector from a noisy humidifier fan.
Unplug the fan connector. The connector might have some hot glue or RTV silicone on it to prevent it from coming loose. You can use something like a box cutter to remove it. If the wires of the fan are soldered to the circuit board, clip the wires instead.
A pair of wire clippers being used to clip a tie wrap that holds several cables together.
Clip any plastic tie wraps with a pair of wire clippers. Take care not to cut any wires by accident.
A hand pulling a dust blower fan out of a humidifier for repair.
Remove the fan. In this humidifier the fan is press-fit and can simply be pulled out. If in your humidifier the fan is mounted with screws, you’ll need to unscrew those first.
Close-up of a centrifugal fan full of dust.
Well, there’s your problem! No wonder the humidifier had gotten louder. I do not expect this fan has a lot of life left, so it is going to be a straight up replacement.
A SANLY SF5015SL DC12V 0.06A blower fan.
At this point, you can check the specific brand and model of the fan. You can find this information on the sticker on the back.
A SANLY SF5015SL next to a SUNON EF50151B3 fan.
If, like me, you can’t find the exact same model, you can get one that is similar. This means the same dimensions (e.g. 40*40*20 mm or 50*50*15 mm (width x height x depth)) and the same voltage (usually 12V). Ideally it would also have a similar airflow, but this is less important.

Good places to source replacement fans are AliExpress, Ebay, RS-online or, if you are located in the EU, TME. Amazon has them as well, but it can be harder to find the right match there.

Cleaning and lubricating the fan

Cleaning and lubricating the humidifier fan is straightforward and will make it run more silent. The effect of this depends on how worn out it is. It typically gives results for a couple of weeks or months before you have to do the process again.

A sticker being peeled off of the back of a blower fan to expose its axle and bearing.
Partly peel the sticker off the back of the fan.
Lubricant being applied to a humidifier fan.
Add a single drop of lubricant into the hole that contains the axle and bearing. You only need a very small amount.
A sticker being pressed on to the back of a radial fan.
Press the partly peeled off sticker back onto the fan.

This is also where you would use canned air to remove any dust from the blades and fan cage.

Notes
  • Manually rotating the fan blades a couple of revolutions helps get the lubricant to all the right spots.
  • On some fans there is no hole under the sticker. In that case, lubricating is not possible and replacement is the only option to get rid of the noise.

After lubricating the fan you can skip ahead to reassembly.

Replacing the fan

Wire clippers being used to cut the power wires on a squirrel cage fan.
Clip the connector from the original fan. We need this to connect the replacement to the circuit board.
A pair of wire strippers that removes the insulation from wires attached to a fan connector.
Use a pair of wire strippers to strip the insulation from both the fan and the connector wires (4 wires total).
Heat shrink being slid over loose wires.
Slide a piece of heat shrink over each of the fan wires.
Two copper wires with black insulation held in a third hand tool for soldering.
Solder each set of red and black wires together. A set of helping hands can be useful for this step.
A hot air gun heating up heat shrink to reduce its diameter.
Shrink the heatshrink by heating it up. I used a hot air rework station for this, but you can also use something like a lighter.

Reassembly

A variety of connectors and plugs on the inside of a loud humidifier that is being fixed.
Reattach the fan connector.
A hot glue gun applying glue to a a two-pin connector and header on a circuit board.
If you want to be sure that the connector does not come loose due to vibrations, you can apply a dab of hot glue to keep it in place. Usually it is fine without any hot glue.
A variety of electronic components in a Levoit LV550HH humidifier.
Reseat the fan in its mounting location. If the fan is press-fit you can also use a bit of hot glue to secure it better.
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Make sure that the fan is oriented correctly! This usually means that it blows upwards through a hole that it lines up with.
A tie wrap holding a bunch of electric wiring inside of a repaired humidifier..
Replace any tie wraps that you have clipped off. We don’t want any loose wires to end up against things like heating elements.

From here on, it is just a matter of reassembling the device in the opposite order of disassembly. Put the bottom panel back on, drive the screws back in, and so on.

Notes
  • When putting the feet back on they usually still stick well enough by themselves. If not, some hot glue or a piece of double sided tape will keep them in place.
Bonus
A partially disassembled blower fan that has been completely ruined by dust.
The insides of the original fan. Given how many hours humidifiers spend sucking in air (and dust), they should really come with a built-in dust filter. It would significantly increase their lifespan.

FAQ

What sound is my humidifier supposed to make?

You can expect your humidifier to make a mild humming or buzzing sound. Either is perfectly normal. Grinding, buzzing or rattling is a concern, however. The same goes for other new, loud noises that were not there before.

Are gurgling sounds normal?

Yes, this occasionally happens when water from the tank flows into the base of the humidifier.

Why is my humidifier so loud?

If the humidifier only recently became loud, it is because one or more components need maintenance and/or cleaning. The sections above have instructions on how you can do this yourself. If the device has always been loud, it probably just is a loud model.

Conclusion

If your humidifier got louder or started to make an annoying noise, you do not need to throw it out and buy a new one. A good clean of the base and lubrication of the fan is often enough to give the device new life.

Even in severe cases of wear, like when the humidifier has started to make a grinding or buzzing noise, you can fix it yourself. Most likely you will have to replace the fan, but this is fairly simple if you follow the repair guide above.

If you find this article useful, please share it or leave a comment. I love to hear your feedback and questions!

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