Humidifier Saying Waterless, Even When Full? Here’s Why

Humidifier Saying Waterless, Even When Full

Have you ever had a moment where you think an appliance is deliberately playing mind games with you?  Maybe it’s the oven you swore you turned on to preheat only to find out it’s not on.

Or the dryer that you turned on, even heard it buzz to indicate it was done with the cycle, only to find the clothes still wet and nothing warm inside.  Kind of like you never turned it on.

Notice a pattern here?

You may think your appliances are playing mind games with you but in all actuality, you forgot to turn them on.  Or didn’t press the ON button enough for it to full turn on.

The same holds true for your humidifier and the WATERLESS indicator you’re getting.  After all, you literally just filled the tank and put it back on the humidifier.  You’re even looking at it and clearly see water in the tank.  There’s no way you messed this one up and forgot to add water.

And you’re right.  You didn’t forget the water.  Your humidifier, though, isn’t recognizing the presence of water, which is an issue.  If it doesn’t think there’s water, it’ll shut off and your call for humidity will go unheard.

Don’t think of it as a mind game, just a puzzle that needs to be solved.

Now it’s time for you to take a look at a couple of things that may explain why your humidifier is saying WATERLESS when it’s full and what you can do to correct it.

What you can do to solve the puzzle.

1. There is No Water in the Tank

First things first.  Is there water in the tank?

Now you may be wondering, “I thought you covered that in the introduction.  You said it’s a puzzle that needs to be solved.  Clearly, the tank is full of water.”

Right, right.  Yes, there’s water in the tank.  It’s only asked here because that’s the first thing 99% of manufacturer manuals will say when it comes to why the WATERLESS indicator is on.

Don’t take it personally.  It had to be asked even though the answer was already known.

But, did you double check just in case there wasn’t water in the tank?

Moving on.

Hands Filling Humidifier With Water
First things first: did you remember to charge your humidifier with water?

2. The Floater isn’t Functioning

The next thing a manufacturer’s manual might say is the floater is stuck, like this same manual does.

The floater mechanism between the well (or base) and the tank does what it sounds like it does.  It floats.

However, for it to float water has to be present.  When the water in the tank runs out, the floater should drop, indicating to the humidifier’s brain that it’s time to shut off until water is replenished.

However, if water is present but the floater isn’t floating, then more than likely it’s stuck or jammed.  It should take minimal effort to free it.

If you’re doing your daily cleaning (like you should be when using your humidifier) you can always do an inspection of the floater to make sure it has free movement and is clean as well.

3. Spring Valve Stuck

Because humidifiers vary greatly both in manufacturers and varieties, one answer to a problem may be more appropriate for your model than another.  If you don’t have a floater on your humidifier, you may have a spring valve.

The spring valve on some models resides between the tank and the base.  When the tank is of the base, the spring valve keeps the tank closed at the bottom for refilling and prevent leaks.

Once the tank is placed on the base, the spring valve should activate and allow water to move from the tank to the base and ultimately the rest of the humidifier.

If the spring valve is stuck, water may not flow from the tank.  If the humidifier isn’t sensing water in the base, it’ll assume there’s no water and the tank needs to be refilled.

Another issue with a spring valve may not be that it’s stuck but that it’s tight and needs a little more pressure when seated to activate it.  To do this, you can always try the old fashioned “jiggle” method.

The spring valve should be relatively easy to free.  However, if you remove the tank and it’s leaking at the spring valve, you may have a damaged valve or gasket that needs replacing.

4.  You Need to Do Some Cleaning and Maintenance

This isn’t necessarily a fix for your humidifier indicating WATERLESS issue.  But when lights and indicators start going off for no apparent reason, it’s always good to clean the unit in case any dirt or gunk is affecting an appliance’s normal operation.

You may not think it’s helpful but you’d be surprised how one thing can affect another and then another and the next thing you know, your machine thinks it’s out of water when it’s not.

The need to do any kind of troubleshooting is a perfect excuse to do some well earned cleaning and maintenance.

If you’ve got a dryer that needs to be worked on, it’s always good to clean the exhaust of lint because the last thing you want is your problem to be a clogged dryer exhaust.

With humidifiers, dirt, debris, hard water, and mold can all impact the performance of your unit.  That’s why it’s recommended to clean them often.  Not just for your health but to ensure they keep working and don’t start having faults that may require more professional repairs.

Besides doing the normal cleaning, disinfect it, per the manufacturer’s guidance.  Look for and scrub away any scale.  Inspect your power cord, making sure it’s free of damage or abrasions.  Check your plug and make sure it’s not damaged or bent beyond repair.

When all that is done, refill the tank. 

Hands Cleanning Water Tank From Humidifier
A dirty humidifier can be a breeding ground for bacteria and mold, and if they start growing in a humidifier, they get sent out into the air and you can breathe them in.

5.  Plug Your Humidifier into a Different Outlet

If you’ve had your humidifier unplugged for cleaning and disinfecting, it should have been unplugged for a good 30 minutes or so.  This is the recommended time some manufacturers recommend to allow for a humidifier to RESET.

Will it work to clear your WATERLESS indicator?  Maybe.  Then again, so may the cleaning and disinfecting.

One other thing you may want to do is try plugging the humidifier into a different outlet.  You can do this after cleaning and disinfecting or it can be the first thing you try.

Electrical appliances can be touchy sometimes and if there’s competition for power from the outlet, well, the humidifier might not be getting all the energy it needs to function correctly.

Also, don’t plug your humidifier into a power strip.  Instead, try plugging it into an outlet only it is using.  If the WATERLESS indicator goes out, then it may have been an outlet or power strip issue all along.

6.  When to Call for Help

If you try all of the recommendations presented here and none of them work, you should probably call for help.  Most manufacturers have a customer service line that can help and may provide more specific recommendations for your particular model.

Or, as in this case, Dyson chose to send the customer a whole new humidifier when they didn’t have any good answers.

You might not get a whole new humidifier but when customer service doesn’t have good answers, you know you may need to take it to a professional for further diagnosing.


A humidifier telling you it’s WATERLESS or empty isn’t a functioning humidifier.  If your water tank is full and it’s still telling you it’s WATERLESS, you’ve got a humidifier that needs some help to overcome its confusion.

The reasons your humidifier may be acting this way aren’t complicated and the fixes are usually pretty simple (although not as simple as refilling the tank with water).

However, if the simple fixes don’t get your humidifier up and running normally, then you may need some professional help to get the right answer.

I've been helping homeowners with appliance repair since 2016. Starting out as an enthusiastic amateur, I've since worked with many Appliance, HVAC, and DIY experts over the last 7+ years. My mission is to help fix your appliances and prevent future issues - saving you stress, time, and money. Visit my author page to learn more! Read more