Informational Guide

Ultrasonic Humidifier Not Working?

What do you do if your ultrasonic humidifier isn’t working correctly? Troubleshoot common problems with our complete guide.

by Josh M

Keeping your humidifier in good condition will not only help it last for many years but will also help it work effectively.

Humidifiers are excellent ways to avoid dry winter months and problems from dry air such as allergies, asthma, difficulty sleeping, snoring, and nose irritation.

So what do you do if your ultrasonic humidifier isn’t working? To troubleshoot common problems with your ultrasonic humidifier, read this guide.

Dehumidy Room

Ultrasonic humidifiers are like any other home device and can encounter problems. Most ultrasonic humidifiers and evaporative humidifiers last approximately two to six years, but taking care of them will help them last longer.

Not working at all

If your device is not working at all, join the club. This is a common problem that homeowners face. The best solution for this problem is to start with a thorough cleaning. It is easy to put off cleaning your humidifier when your life is hectic.

We recommend cleaning the humidifier thoroughly, including taking the tank out and cleaning the internal membrane.

Not producing any mist

Another common problem is a humidifier that is not producing any mist. This typically signals a problem with the internal membrane. This problem is difficult to fix and depends on the type of unit that you have.

We recommend looking at your particular unit’s instruction manuals to figure out where the mist valves are and ensure that they are free and clear. This is an issue that is often covered by the manufacturer’s warranty.


If your appliance is leaking, then the problem has to do with the valves, tubes, or tank. One of these areas has a hole, crack, or other opening that is allowing water to spill out. Trying to troubleshoot this issue involves running the humidifier and watching what areas leak.

Your best bet will be to purchase a replacement part for whatever part of the humidifier is leaking.

Humidistat sensor issues

The humidistat sensor issue is typically an electrical issue. If your sensor is not working and cannot properly adjust the humidity levels, then you need to bring the device in for a replacement sensor. Depending on the cost and depending on your warranty, you may choose to replace the humidifier instead.

Bad odor

A foul odor is a sign that your humidifier is due for a cleaning. We recommend taking apart your humidifier piece-by-piece and cleaning it. Using vinegar as a cleaning solution may help you get rid of the smell.

You also may want to spritz a fragrance around the humidifier when finished cleaning, but don’t skip the cleaning step! If you do not clean your device, bacteria may continue to breed, creating an unhygienic environment.

Making a lot of noise

If your humidifier makes a lot of noise, there are numerous problems that could be to blame. The most common problem is going to be that screws are loose, and the device is no longer being held together correctly. Disassembling the humidifier and tightening each screw should be your first step when troubleshooting this problem.

How To Repair An Ultrasonic Humidifier: Step By Step

Cozy Bed and Wooden Bedside Table with Stack of BooksIt is possible in many cases to repair your own ultrasonic humidifier at home. There are a few tips and tricks you can try to repair yours.

You will need vinegar or another cleaning solution, several washcloths, and several q-tips.

To begin, make sure that you unplug the device. Once your humidifier is unplugged, take the water tank and empty it into a nearby sink.

Next, turn the humidifier on. The trick is to pay attention to what happens when you do. Do you see water droplets moving? Is there a little bit of mist generated?

If you see this, then you know that the humidifier is working internally, and the issue resides in the main water tank.

Thoroughly clean and review the entrances and exits on the main water tank using the vinegar (or other cleaning solution) and washcloths.

If you do not see water droplets or mist, then there is something wrong with the internal membrane. Clean the membrane (typically a round, circular plate). Make sure that there isn’t any lime, crud, or other debris in this area. Often mineral deposits build up inside the internal membrane and create problems. You can use q-tips here.

Finally, put the humidifier back together, fill up the main water tank, and turn it on.

When Is It Time To Replace Your Ultrasonic Humidifier?

It is time to replace your ultrasonic humidifier when you notice that the unit isn’t working, isn’t performing at full capacity, or there are additional features you want on a newer model. Ultrasonic humidifiers tend to last approximately two to six years.

  • Clogged tubes
    A clogged tube inside your device may make it difficult to use. You may find that the mist comes out a different color or has a smell. You may find that very little mist comes out (perhaps 10% of the previous mist output) because of the clogged tubes. It isn’t easy to take your device apart and clean each individual tube. In many cases, we recommend that these humidifiers be replaced.
  • No power
    If your humidifier will not turn on and you cannot get a power signal, then there is a good chance that the problem is electrical or hardware-based. Both of these issues require an expert to fix, and it is typically much cheaper to simply replace the unit.
  • No obvious issues and out of warranty
    Some homeowners prefer to replace their ultrasonic humidifier when the unit runs out of warranty. This makes the most sense when you realize that your unit isn’t working properly, there isn’t any apparent reason why, and the unit is out of warranty.

Troubleshoot Different Ultrasonic Humidifier Brands

Honeywell Model Not Working

White & Grey HumidiferIf your Honeywell humidifier model is not working, we recommend visiting the Honeywell manufacturing website to learn more.

One common tip mentioned by many Honeywell users is to turn the moisture control knob all the way up. At the highest level, the humidifier should reset. Let it run for thirty minutes, and then turn it off. Unplug it, plug it back in, and see if it works.

Homedics Model Not Working

If your Homedics humidifier model is not working, we recommend visiting the Homedics manufacturing website to learn more.

One standard tip we encountered with Homedics humidifiers is to ensure that you properly clean the humidifier weekly. Some users noticed that when the humidifier hadn’t been cleaned in a while, it had problems with auto-shutoff and other features.

Crane Model Not Working

If your Crane humidifier model is not working, we recommend visiting the Crane manufacturing website to learn more. A common issue with Crane humidifiers has to do with the water tank cap.

If the water tank cap is not secured and fastened properly, the unit will not turn on. If your power light on the device is red and not green, try fastening the cap securely.

Check out our Crane humidifier reviews

Pureguardian Model Not Working

If your Pureguardian humidifier model is not working, we recommend visiting the Pureguardian manufacturing website to learn more. Several homeowners noted that their Pureguardian models stopped working because of the crud that accumulated around screws inside the unit.

Make sure that when you are cleaning, you clean around the various screws, buttons, and other materials, not just the inside of the tank.

People Also Ask (FAQ)

Can you use tap water in a humidifier?

You can use tap water in your humidifier, but it is not recommended. Most humidifiers function better with distilled water because tap water often has microorganisms in them that are unhealthy for you.

This can lead to bacteria being spread into your home through the air, according to the EPA. Use distilled water, and you won’t need to worry about this problem.

Do humidifiers use a lot of electricity?

No. Modern humidifiers use very little electricity while running. They were designed to be energy efficient, and you should only spend between $2 and $30 running your humidifier each month (even if you run it 24/7!)

Can I put vinegar in my humidifier?

Yes and no. Yes, you can use vinegar to clean your humidifier, but no, you should not put it in your humidifier long-term. In other words, clean the tank with vinegar and then rinse it out thoroughly before adding your distilled water to the tank and running it again.

Is sleeping with an ultrasonic humidifier a good idea?

Yes, sleeping with an ultrasonic humidifier is a great idea because it can help you sleep better. Ultrasonic humidifiers moisturize the air around you, which in turn helps keep your airways moist so that you can breathe better without coughing or snoring. This leads to more restful sleep.


Taking care of your ultrasonic humidifier will ensure that it lasts for years and provides comfort to your family. Setting aside the time to properly clean your humidifier and troubleshoot any issues you find will keep it running smoothly. Enjoy your clean air and keep your airways moisturized, skin soft, and air virus-free.

Last Updated on December 20, 2022

Josh M

My name is Josh and I am obsessed with the HVAC industry. I created this website to help HVAC techs of all levels get the best out of their heating & cooling systems. I have spent thousands of hours studying air conditioners, heaters and home air products so you can learn & buy with confidence. Learn more about the team here.