Ultrasonic Humidifier Not Working? Troubleshooting Guide

An ultrasonic humidifier will not work in case it hasn’t been assembled correctly and in case the diaphragm is blocked. Make sure to follow the instructions, when putting the humidifier together and don’t forget to clean the device at least once a week to avoid any type of buildup.

How do you troubleshoot an ultrasonic humidifier? Is it even worth it or should you simply buy a new device instead?

Here are the answers you’ve been looking for. 

What Is an Ultrasonic Humidifier?

Unlike regular humidifiers, an ultrasonic one uses sound vibrations of an extremely high frequency to produce a fine mist that increases the humidity level in the room.

An ultrasonic humidifier consists of a water reservoir and a diaphragm (or another vibrating element). This element vibrates at a high frequency and expels microscopic droplets into the air.

Fact: such humidifiers can be called ‘cool mist humidifiers’ as there are no heating elements within the system.

Evaporative humidifiers can also be ‘cool mist humidifiers’. However, unlike evaporative devices, ultrasonic humidifiers do not produce water vapor inside the unit, they simply send water droplets into the air.

In a nutshell, the vibrating element is able to create waves that are so strong that they ‘kick out’ the molecules of water out of the humidifier and into the room.

The main benefits of an ultrasonic humidifier are that it does a great job at increasing the humidity level, it is quieter than an evaporative humidifier, it can be made very small, and it consumes little electricity.

Read: Signs Of High Humidity In Your Home

Ultrasonic Humidifier Not Working – Possible Reasons

Due to the fact that an ultrasonic humidifier is an extremely simple device, there are not that many things that can go wrong.

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So, if your unit is not working, the chances are high that the problem is…

A Blocked Diaphragm

The diaphragm or another vibrating element will get dirty over time if the homeowner doesn’t stick to a cleaning schedule.

If you have been using your humidifier for quite a while already, the diaphragm can get clogged by dirt. At times, insects can make their way into the device.

When something like that happens, the humidifier will first start to produce less mist and, if the problem persists, it will stop working at all.

An Incorrect Set-Up

It is incredibly important to set up any device correctly. Otherwise, the unit will fail to work.

Make sure that the humidifier is placed on an even surface, that the water tank was put directly into the base, and that the power cord is not damaged.

It is always better to consult the manufacturer’s instructions when assembling a new device.

The most common problem is an incorrectly placed water tank. If you can’t hear water flowing after you have switched the device on, then take the tank out and try inserting it correctly.

A Defective Device

If it’s your first time using your ultrasonic humidifier and you can’t seem to make it work, then there is a chance that the actual device is defective.

Most reputable manufacturers offer a warranty, so you can always ask for a refund or a new unit.

Read: Why Do Humidifiers Need Distilled Water?

How to Troubleshoot an Ultrasonic Humidifier?

Here are a few things that you can do to fix your ultrasonic humidifier.

  • Inspect the device. Make sure that the control light is green, the tank has enough water, and that the reservoir below the tank is full.
  • If everything seems to be okay, then it looks like the membrane is blocked. This can be because of limescale, mineral buildup, or even drowned insects.
  • You can easily check, if there is something blocking the outlets for the water. Simply remove the water tank and turn your humidifier on – if you see drops jumping out and a bit of fog above the surface, then the unit is working correctly.
  • You would have to check the water tank for any obstructions.
  • If you didn’t spot any fog above the water surface, then unplug the unit and inspect the inside tank. 
  • Then find the membrane. Usually, it looks like a rubber plate located inside a round frame.
  • Examine the tank and the membrane. If you spot any limescale or debris, you would have to clean the inside of the unit.
  • You can use a hose or simple tap water to wash out the dirt from the frame and the membrane.

Warning! Do not touch or clean the electrical parts of the humidifier. Before reassembling the unit, make sure that it is dry. 

Other Common Ultrasonic Humidifier Issues

  • Bad odor

If you have noticed an unpleasant smell coming out of your humidifier, then it’s time to give the little helper a clean. Take the unit apart and clean all of the pieces (you can use a cleaning solution or vinegar).

  • Noise

In general, ultrasonic humidifiers are very quiet as they don’t have a fan. But even these silent devices come become noisy, if the screws become loose.

In such a case, all you would have to do is tighten the screws and reassemble the unit.

  • Leaking

If you have found a puddle around your humidifier, then there is a leak in the valves, tank, or tubes. You can turn the humidifier on and then try to figure out where the water is coming from.

The only thing that you can really do, if you have spotted a hole or a crack in one of the components, is get a replacement part.

  • Humidistat sensor issues

Experts recommend getting an ultrasonic humidifier together with a humidistat, as the latter is going to help control the humidity levels (ultrasonic humidifiers can make the humidity in your room skyrocket, if not regulated). 

Unfortunately, if you have noticed that the humidistat can no longer make the correct readings, then you would have to replace the sensor. 

Sometimes, it’s easier to replace the whole humidifier as the cost of a new sensor can be mind-blowingly high.

Read: Why Is Humidity Higher Inside Than Outside?

How Long Do Ultrasonic Humidifiers Last?

Portable humidifiers usually last anywhere between 2 and 5 years. Of course, the lifespan of your unit is going to depend on the quality of maintenance. 

As an ultrasonic humidifier doesn’t have a heating element, it is not able to kill any bacteria present in the water. That’s why experts recommend using distilled water instead of tap water (this will also prolong the life of your device).

Make sure not to leave any water in the tank when the humidifier is not in use.

Ideally, you would want to clean the device at least once a week.

You can soak the water tank in a vinegar solution for around 20 minutes. Use a soft brush to get rid of the film on the surface of the reservoir; if there are any stains, you can try using a tooth brush. 

Bear in mind that if your humidifier does not have a ceramic-type cartridge, the unit might be producing a fine grayish dust that is going to settle around the room, when the device is in use.

This will happen because an ultrasonic humidifier doesn’t have a filter to absorb the minerals in the water.

Read: Whole House Humidifier Problems You Need To Know

When Should You Replace an Ultrasonic Humidifier?

If you have tried out all of the tips mentioned above and your ultrasonic humidifier is still not working, then, perhaps, the time has come to replace the unit.

If you have noticed any of these issues, then getting a new humidifier might be a quicker and cheaper option.

  • The tubes are clogged

If one of the tubes inside the unit is clogged, the device won’t be able to work at full capacity. In fact, it might stop operating at all (or the water can come out a strange color and have a smell).

Even though a clogged tube might seem like an easy fix, it is very challenging and time-consuming to take the humidifier apart and clean every single tube.

  • There is no power signal

If the humidifier will not turn on at all and you cannot see a light on the device, then there is an electrical issue. In the majority of cases, only an expert would be able to fix it.

At times, replacing an electrical component will cost you as much as a new humidifier, so getting a brand-new device might be a smarter decision. 

  • The unit ran out of warranty

Even if there are no obvious issues with your device, you might want to consider replacing it, if the unit had run out of warranty. 

Read: Whole House Furnace Humidifier: Everything You Need To Know