Why Is My Humidifier Not Producing Mist & How To Fix It?

A humidifier is a useful small appliance at home to make you feel comfortable. But it is also something that can go wrong at some point in your life. A common problem is there is no mist coming out of it. 

Don’t be agitated! Fixing a humidifier that is not producing mist is not as challenging as expected. I will summarize six possible reasons and corresponding solutions in the following sections to help you get your humidifier to work again in a few minutes.

Why is there no mist coming out of my humidifier? 

Humidifiers work to increase humidity by propelling water vapor into the air. If you can’t see any mist coming out of the humidifier, there should be something wrong with it.

Luckily, these issues are easy to fix, and I offer solutions for each problem below.

1. No or low power

Sometimes, the problem is not related to the machine itself. The breaker may flip into the fuse if you live in an old house due to the high-powered humidifier. Or the cord is not fully plugged into the outlet.   

Whenever you find the light is not on, or the motor is not working, it may be due to the power source.  

You can test it by plugging another working appliance into the outlet. If it is not working, the problem is confirmed, and you need to hire an electrician to fix it. Otherwise, there may be some electrical issues in your humidifier.   

For a humidifier that is still under warranty, you should make use of it and send it to the manufacturer. Going to the local repair shop is also a sensible idea. 

2. Run out of water

If you leave your humidifier on for a long time, it will run out of water eventually. When the humidifier lacks water, it will shut off and stop producing any mist. 

Most modern humidifiers have an automatic shut-off feature. Therefore, it would not be problematic to forget to refill the tank. However, if it is broken or doesn’t have this function, the plastic part may melt or even catch fire. 

Fixing this issue is pretty straightforward. Once you refill the tank, it will start to work again within a few minutes. 

I understand that for many people filling the tank is a chore. You could solve this problem by choosing one with high capacity or installing a whole-house humidifier. 

3. It is clogged

The air drawn in by the built-in fan will blow through the moist wick filters in an evaporative humidifier and then evaporate into the air as mist. 

Even though manufacturers advise you to use distilled water, many people continue to use tap water that contains many minerals and other debris. 

With time, the filter will become clogged, so the air can’t get through the filter quickly, causing the mist not to come out. You can get it to work again by installing a new replacement filter. 

Other types of humidifiers will also face the same issue. Ultrasonic humidifiers don’t have filters, but the mineral buildups can block the vibrating membrane.

Warm mist humidifiers use a heating element to produce steam. The mineral buildups will accumulate and build a layer of insulation outside the heating element, making the water turning into steam more difficult.

Therefore, you should remove the buildup in the basement and tank regularly. Undiluted vinegar is an excellent solution to remove debris and limescale. Then you can use a toothbrush or soft cloth to wipe away the deposits. Don’t forget to wash off and keep the tank dry while not in use. 

You may need to chip the mineral layer off with your fingers or other tools for a warm mist humidifier. Deal with it carefully to protect the heating element inside.

4. Humidity setting problems

wrong humidity setting

Some humidifiers could let you set how much humidity you want in the room, meaning that it will stop working or won’t turn on whenever the room humidity is above the level you set. For instance, you set it at a 30% level, but the room humidity is 35%. 

Installing a hydrostat is the best way to fix this issue. Once you know the room humidity exactly, you will not set up the humidity level mistakenly. There are some methods to measure the room humidity level without a hygrometer if you can’t get it immediately.

5. Not level

The anti-tip feature is a useful function for families with kids and pets. When humidity is not placed at an even surface or not level, it will stop producing mist to prevent possible accidents. 

Finding an even place for your humidifier can fix this problem immediately. 

6. Mist is not visible

Not every humidifier will produce visible mist. Evaporative humidifiers employ mist-free technology to add moisture to the air, which differs from ultrasonic ones.

It means your humidifier is working, and you just can’t see the mist. 

To ensure the unit is in a good state, you can fill the water tank and observe if the water level goes down after one or two hours. If it is the case, your item should constantly be working.

Another way to test is checking the humidity level through a hydrometer. If the humidity level increases, there is nothing wrong with the unit.

Ways to keep mist coming out of your humidifier continuously

Having a humidifier that stops producing mist periodically is annoying. Everyone wants their appliances can work constantly. There are a few ways that can help you out.

1. Find a trustworthy product

Ideally, you can expect your humidifier to last two to five years. But I find that some flimsy items can only last for a few months. Therefore, I suggest you get a product from a trustworthy brand with a good warranty even though you may have to pay a bit more upfront. 

2. Clean your humidifier regularly

The mineral deposit is the main reason why there is no mist coming out. Therefore, you should clean the basement and water tank regardless of which type of humidifier you choose. 

Remember to replace the filter for evaporative humidifier owners. This is also important if you have a cool-mist humidifier because the mineral can go with vapor and land on furniture and electronics, which is hard to remove.

3. Don’t use tap water

Using tap water would not be a big issue in a short time but could shorten the lifespan in the long run. If you use distilled water, nothing in the water will clog the filter or wick, meaning that the mist can freely come out from the machine.


No mist coming out from a humidifier is a common problem for homeowners. Instead of taking it to a professional, you can fix it in many cases. 

The mineral deposit is the main culprit as it can block the filter and wick so that the water can’t turn to be vapor and steam. Using distilled water could help to solve this problem. 

It may also be due to the poor connection or settings. Please don’t set the humidity level too low as it will turn off automatically or even not turn on. 

Read the six reasons I listed above, and you are likely to solve the issue on your own. 

About The Author

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Liz Yang is the founder of Airsmartly. She has been working at home for a few years and realizes that the performance of the HVAC system plays such an important role in our life. She has tested dozens of products in person, like humidifiers, air purifiers, dehumidifiers, and ACs, and wants to share tips about using or troubleshooting these products with you. Her uncle is an HVAC expert with over 30 years of experience in the field, and often offers assistance when she is unsure how to handle a situation. He is also in charge of reviewing the articles on this site.

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