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Question about ultrasonic mist maker

I am using a cheap ultrasonic mist maker for certain thing. My goal is to get as much mist as i can with it. In order for this i need the answer to two questions:

1) What would be the optimal distance between top of the mister and the water level, meaning how far under the water it needs to be to get the max output. If this cannot be answered then how would i go about testing it. I can visualy try to assess it testing different depths but visual inspection of mist is not very accurate.

2) This mist maker has holes in the bottom of it and it has very tiny legs, so that if its on the bottom of water box, there will always be about 1mm of space for water to get in. Does this distance matter ? Because right now i made a system where the mist maker will actualy be floating a few centimeters under the water top. That way no matter how much water i have in the box, it will still be working. But does that negatively affect its performance ?

My goal is to get as much mist i can with given Wattage. This module uses about 12W and with added fan i turn about 0.25L of water per hour into a mist. I would like to increase this amount as much as i can with as electricity usage. I attached an image of the mist maker element.


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Well-Known Member
Whoever designed it did not aim to produce less fog than it is capable of with the recommended water level.
You want more? Use several misters !
Seems you are used to the 'bigger carburetor' 'add a turbo' ways of 'overclocking' and 'push beyond the limit' things for poor longevity and when fail complain is poor quality...
Ohhh, so that would be minimum 4.4cm, maximum 5cm. Thats a lot less difference so it wont really make much difference. I might go for 4.4cm. For some reason i have a feeling that will send more mist out than 5cm, though probably the difference is so small you cant even measure it. Thank you for your help.

Since i have this topic opened another question. In computer fans its more energy and noise efficient if you use 1 big fan rather than 4 small ones (if we compare 4 small fans that put together are as big as 1 big fan). I am wondering if its also the same case with mist maker ? Would it be better to have 1 big mist maker rather than 4 small ones like the one i posted in my first comment ? I am trying to get as much mist as i can with as little power as i can. The mist on the picture uses about 12W and it turns about 0.25L of water into mist with the help of a silent fan blowing the mist out.


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Most Helpful Member
One mist detector used in fast engines, sensed continuously how much light reached the sensor inside the carter. When, for any reason, the vaporized oil mist reduced the amount of light, an alarm was triggered.

BTW, ignoring recurrently this alarm, ended in a 500K U$D crankshaft replacement and some weeks of a ferry out of service.
This mist detector has self protection, on top there is a small metal ring that i am guessing detects when water level is to low (no voltage on that top part im guessing). So it stops working and prevents overheat. The wierdest thing happened with 1 of the misters though. I am using 1 for 2 years now and its working great. But i made a misting device for a friend, the same way i made it for me. And water level was ok at all times ... it died after a few hours. The mist maker actualy died so badly that it was effectively a short circuit - zero resistance. So i was amazed that a cheap 6 dollar aliexpress power suply detected a short and actualy survived. It could end with a fire so that was a good signal to me that i should always use a fuse.

I am back to height problem. We now know i need to use 4.4 - 5cm depth. But is that measured from bottom part of the mist maker or the top part ?


Well-Known Member
as far as i remember the top little bit needs to be above the water line, like a cm or an in or sumthing like that, just give it a dip , you will clearly see when it struggles... i floated mine with cut up pool noodle.


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Most Helpful Member
I read the spec as water depth above the mister to be between 3/16" and 7/16" but it is a little ambiguous. Is there someone that can measure a working one?

Nope. I just have the unit like i posted in my first post. It is very small and has to be completely submerged in order to work. That top thingy, like a thin plastic pin with iron top, that is to alert the unit when there is not enough water so it shuts down the mist unit to prevent overheat and damage
I dont understand what you mean by working unit. I just take a box, pour water in it and put this misting thing in. Then i add a little fan and add a outlet hole and i have a working unit.
I started the thread to ask for an optimal water level. Because as i pour water into it it starts working but then as i add more and more water, there will be less and less mist. So clearly there is a point at which you get most mist out of it. And judging by eye i cant really tell when this point it.

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