I've heard of these but am not sure I've seen them for sale in my area. I assume they're not very common in the US as compressor based models generally make more sense - the advantage of operating down to cold ambient temps really just doesn't matter outside of particular climates. Here in the Midwest our humidity levels in winter plummet, and I joke that the humidity here is consistently wrong - dehumidifiers in the summer, humidifiers in the winter! Right now is one of the few times of the year where I'm not bothering to fiddle with it. I would like to get a hold of one of thse and do some energy consumption comparisons. I like the idea of something quieter, but then again (and this might also have something to do with them apparently being rare here) I have a dehumidifier in the basement and use the HVAC fan to move air throughout the building. Since that's almost a given feature in US homes, we tend to like big, powerful units and put them somewhere the noise isn't a problem. Plus, air conditioning does its own moisture removal, too.
I've used similar units in the US for industrial type uses where complete control of the air temp and humidity is required. Ie clean room environments.
I live in MN and have one of these. There's an "Ivation" brand one for sale on Amazon. I actually use it in the garage in the winter time. I keep it lightly heated (~40F or so) and all the snow that drops off the car creates a ton of moisture in the garage that condenses everywhere. This works really well in those cold temps where a compressor based one will not operate, and as a bonus provides a little bit of heat to the garage.
I bought one on amazon for not too much money. I use it in the basement during the winter when the compressor dehumidifier stops working because it gets too cold down there.
This is such a clever little device! I love how it’s basically a heater that makes water from the air. I wonder if I could use a modified design for project Chickenhole. Perhaps concentrated sunlight instead of electricity?
Since a compressor dehumidifier is just an AC running in a closed room, the simplest solution should be a peltier "cooler" (fans optional). For efficiency it will be hard to beat a compressor, so that leaves this device as a neat in-between for both complexity and power usage?
hey cody, glad to see you following 1 of the best teardown channels on youtube :) also instead of direct solar, why not run a 30 watt panel to a pc fan and however much nichrome it can handle?
Requires humidity in the air for it to operate. Using direct solar heating is interesting but still not much water there to collect. Chickenhole looks pretty arid. TLDR: the difference between Can and Should.
There is at least one company using this desiccant+heat process to market a magic "water from air" product. The irony of all such products is that they only work in humid environments.
Counterpoint: while those are obviously quack products, with global warming disrupting cloud formation, drought is becoming increasingly common in the Great Plains. Quite a lot of humid air simply floats over without condensing into rain. Condensing water on an industrial scale might become a necessity within my lifetime at this rate.
@@cheyannei5983 The heat of transformation needed to condense liquid frm vapor is exactly the same as the power used to boil that same amount of water. Consider the amount of water condensed by an air conditioner. It does make measurable liquid, but the energy cost per gallon is horrendous. Could it be done on an industrial scale? Yes, but you couldn't afford the water produced that way.
Zeolite can also be used for VOC extraction from air. Industrial VOC versions of the zeolite disc in this basic arrangement are commonly 3 meters dia by 50-100cm depth. The adsorption (gas phase to liquid phase) process concentrates VOCs from the air stream and are cleverly called rotary concentraters in the air pollution control industry. The captured and concentrated VOCs are commonly fed into a gas fired burner that provides the heat energy necessary for the heated desorption loop making them rather efficient.
My English isn't very good, so I'm not sure if I understand correctly. Do the VOCs condense in the water taken from the air and are then burned at the end (so the zeolite is clean from VOCs)?
I asked Bard: she says [you are ] describing a process called rotary zeolite adsorption for VOC extraction from air. This process uses a large rotating wheel (disc) made of zeolite, a porous material that can adsorb VOC molecules. The process works as follows: The air to be treated is passed through the zeolite wheel. The VOC molecules in the air are adsorbed by the zeolite, while the clean air exits the wheel. The zeolite wheel is then rotated to the desorption section. In this section, a hot gas stream is passed through the zeolite wheel, causing the VOC molecules to desorb from the zeolite and into the hot gas stream. The hot gas stream containing the concentrated VOCs is then passed to a thermal oxidizer, where the VOCs are destroyed. The zeolite wheel is then rotated back to the adsorption section, and the process starts again. This process is very efficient for VOC extraction from air, because it can concentrate the VOCs into a small volume of gas, which makes it easier and more efficient to destroy the VOCs in the thermal oxidizer. So, to answer your question, the VOCs are not condensed in the water taken from the air. Instead, they are concentrated in a hot gas stream and then destroyed in a thermal oxidizer. This process is a very effective way to remove VOCs from air emissions from industrial facilities. It is widely used in a variety of industries, including automotive manufacturing, printing, and electronics.
TOP TIP for Meaco DD8 (possibly the model in the video) to lessen sludge-formation in the area Clive showed: after removing the bucket, tilt the dehumidifer over onto its righthand side (looking at from the bucket side). This will drain the silly little sump over toward the hole that drains into the bucket. (BONUS, if you happen to own an Ecoair DD1, which isn't the model in the video): For preventing sludge building up in a similar way: after removing the bucket, tilt up the dehumidifier toward the closed short edge (the end opposite where the bucket aperture is) and slightly to the left as you look down into the bucket-hole. This will overflow the collected water from where it collects and allow it to drain over the plastic plate above where the bucket goes; you'll see a stream of water trickling down to that now bottom corner. Jiggle the unit as you tilt it to maximise drainage. I soak up this water with a cloth and repeat until the stream stops. It is always a surprising amount. Edit: just to say, desiccant dehumidifiers are absolutely the way forward for clothes-drying indoors in damp winters. They may seemingly use a lot of energy, but their 'waste' product is heat, which nicely warms the room they're used in. Also, GREAT video, Clive!
Bought one of this type four of five years ago after I saw a previous video of yours on one and it still works great for drying clothes gently here in wet-ish Seattle. Maybe time to open mine up and see how bad it is on the slime front... Thanks for the reminder Clive!
Interesting. Never seen one of these as an ambient air dehumidifier, though, I’ve worked on quite a few that are compressed air dryers. Look up Atlas Copco’s MD Dryer operation. Same principle, but uses heat of compression from an oil free compressor (typically 75kw/100hp and up) for the regeneration process. When sized correctly, it’s an efficient way to dry the air and usually better (lower dew point) than a refrigerated dryer can achieve. Thanks for sharing
Thanks for telling us this info ... we use hydrovanes without dehumidifiers - but on look out for one .... need to do some research here. Slàinte Mhath.
If you heat a mass of cold air, you automatically dehumidify it. The actual amount of water vapor remains the same, but the RH value which is the direct measure of humidity decreases. However, if you cool a given mass of warm air, you must remove excess water because the air becomes saturated with water very quickly if you cool it.
@@CyberlightFG all the moisture is trapped by the gel but the gel must be dehumidified periodically. That step is not done well. Without that it won't work well.
Where I work we have several very large versions of this. The drums are about 6 foot in diameter. Got to see one of the drums get replaced due to 20 years or so of usage. It had been eaten away pretty badly and was very clogged. Still a very good and simple tech for what it does.
I have 2 of these ... solved all my winter mould problems ... just brilliant ... buy a meter that shows humidity once the house gets down to 45% no point running them any longer ...
I'm from the high deserts of Colorado, and we have low humidity year-round. My first work trip sent me to Texas / Louisiana border next to the Golf Coast, and the hotel room had a loud dehumidifier. After talking with my Sister, who lived in Texas and Florida, she said everyone just ran the AC all the time. Clive had a dehumidifier video out at the same time talking about warming up the room some to have better results. I raised the room temp, and the dehumidifier quieted down, and in one night, it pulled about a gallon of water out of the air in the hotel room. I also remember going out at 6:30. The sun was starting to come up, and it was already hot, and I felt like the air was so thick it was suffocating me. I was glad to return to the dry air from home, where we cool the air with swamp coolers, evaporating water over shaved aspen pads.
I have 2 of each type. Had to replace several dodgy motor caps in the Delonghi compressor type. Another problem is the humidity sensors, probably due to a buildup of fluff around them. In general though I do prefer the desiccant dehumidifiers as they're quieter and have better air filtration and the ones we have incorporate a timer for 2,4 and 8 hours of operation. Regardless of the type it is remarkable how much water they can pull out of the air in a sealed room. One other tip, these are great for drying clothes.
One thing about desiccant drums is that they are more scalable. We use one to dry ambient air before it goes in to a large reactor building. Of course it helps have a fixed unit and can separate the air path for the hot, humid air.
im a hvac tech really enjoyed this and always wondered how these work all though ive only ever seen a couple on site but good to know they are a alternitive in cool enviroments where evaporator coils dont dehumidifie well.
When my wife was at the end of her life, she used a zeolite-based home oxygen concentrator that worked in a similar way. Instead of using heat to drive out the humidity, it had two zeolite-filled pressure cylinders which were alternately pumped up to 2.5 atm to get the zeolite honeycomb to absorb nitrogen. The pressure was then released and the nitrogen-poor (and oxygen-rich) air was pumped through a face mask. It would then switch the cycle to the other cylinder and let the first cylinder return to atmospheric pressure, releasing its stored nitrogen and ready to start the cycle again.
this is the idea used in common oxygen concentrators used in hospitals. They were in great demand during the Covid pandemic. But the actual zeolite used appears to be a trade secret.
My grandfather has a machine by his bed that sound exactly like what you're describing - I think it helped with sleep apnoea near the end of his life. I never knew how it worked! Thanks so much for sharing your knowledge.
At the peak of the pandemic, India began to run short of oxygen for medical use. So there was a crash government programme to make more zeolite oxygen concentrators. Here a video on the operating principles of the two-cylinder type, used for both domestic and hospital units ruclips.net/video/AE5QOq-HN3U/видео.html
Thanks Clive! This helped me fix my desiccant dehumidifier. It had started to make strange noises and one day all the washing it was drying was covered in what turned out to be tiny mica flakes. The sump had blocked with slime as you suggested and the hot air blower fan had been paddling through the water. Some water had been flung up into the heating element and that needed drying with a hot air gun and also blowing out all the loose mica flakes. Unfortunately my model did need to be disassembled to get access to the sump to clean it out. Simple they may be, but for the significant amount of cable spaghetti inside with all those sensors; not easy to disconnect all the bits that needed to come out, but it is working fine again now.
I'd say that the compressor based dehumidifiers have the downside of more noise, and you also have refrigerant that can leak. But these desiccant based ones seem to require much more monitoring and maintenance if you want them to last.
I always enjoy your very knowledgeable insights on electronics and gadgets, I've been spending a lot of time for my other hobbies like art and making ramen completely from scratch.
Thank you for the video on Dessicant air dryer adsorption moisture zeolite cold air honeycomb mesh absorber home quiet household dehumidifier machine. I've got storage in a unheated building. I put a very big bucket with road salt in. (Mesh bucket with salt in a coffee bag over a construction bucket underneath.) Thats effective and very cheap. But that's still not enough to keep it dry. Some people overfill it and it makes a huge mess of saltwater.
Live on the west coast of Canada and only run the dehumidifier in the winter. Helps heat the room and as a bonus drops the humidity levels and keeps the windows drier on the inside.
I once had to change a 9ft diameter desiccant drum at a plastic factory in Banbury. It used Gas burners as electric heaters weren't powerful enough. It was made by a company called Munters.
I've got a similar one bought on Amazon UK three years ago. Called "Ecoair DD1 simple desiccant dehumidifier", it cost 130ukp at the time. It's been very good. Though it's made in China it is ideally suited to the British climate in winter, that is damp cold air. I also live by the sea, adding to the humidity, and in a mid Victorian solid brick home which tends to get damp in winter. The Ecoair's stated operating range is 1 degree C to 35 degrees C. I also bought a Thermopro digital hygrometer at the same time. This measures air dampness accurately, so I can turn on the dehumidifier if relative humidity inside strays too high. The dehumidifier is also helpful if you are trying to dry clothes indoors, speeding things up considerably. However, it would not be suitable for a hot humid climate, as the Zeolite-based drying process heats the air. And in places with cold dry winters you're unlikely to need one, as you could probably get rid of internal condensation simply by better ventilation. UPDATE: just found a Big Clive video from two years ago taking this exact Ecoair model apart ruclips.net/video/BUJqUapiNEc/видео.html. It also goes into the interesting Zeolite desiccant air drying process some more, and the kind of things that can go wrong. But basically the Ecoair seems to be a cost effective, durable device if you live in the type of climate (cold, damp) where dessicant dehumidifiers beat the more widely available refrigerator-like compressor type (better in hot damp conditions).
EBay version: low power saving dehumidifier magic fan heater safe uk plug. Features: 240v case, no earthing, only uses 5w, low power no heating element, magic fan, available colours blue, pink, black, random (colour may be different due to monitor) only available in green.
I live in an area where humidifiers and dehumidifiers are not really necessary (aside from maybe a handful of days every year) so I don’t think I’ve ever seen one of these before. I have a portable AC unit which has a dehumidifier function that I use occasionally during the short periods we have where it is mild temperatures and very humid.
I have had 2 dehumidifiers, the first was a desiccant and the latest is a compressor. In use the desiccant pulled out moisture much quicker than the compressor, although I haven’t checked the comparative energy use per litre...
My wife had an amazing idea earlier this year. We bought a dehumidifier to help us deal with some air conditioning issues over summer. We normally use distilled water in our humidifiers over wintertime, so we don't have to contend with calcium scale (our water is fairly hard). So... put the condensate from the dehumidifier in the distiller, and store it for the wintertime. Obviously, while all stages of this use electrical power, it's nothing we wouldn't be running anyway, and I'd bet it cuts down our tap water use a bit. Never hurts having drinkable water on standby either.
Just be aware that distilled water from AC condensate is considered corrosive, it can eat away copper or aluminum. I don't know what makes it so, but check the pH before drinking or putting it into the humidifier!
I fixed one of these recently, where the regeneration fan motor bearings had stopped working properly. They are quite odd -- they hadn't worn out, but the self-alignment spring was a bit loose causing the actual bearing to wobble around. It looks a lot easier to get apart if you lop all the wires off first!
Ah, temperature swing adsorption dehumidification. Used extensively in large volume dehumidification like hockey rinks. The efficiency scales down too so these small room units are quite useful. Condensing surfaces grow slime with the cleanest air since bacteria only need water and a carbon source. With that warmth, several pathogens are possible including Legionella. The smaller blower motor is the typical shielded pole motor, I know it well as my 4 l water distiller uses a near identical copy. I've relubricated its bearings yearly for the past 10 years. From it, I get distilled water at pennies a liter and free, gentle heat for the bathroom. Far easier to clean the distiller than the water kettle, coffee maker and steam iron.
I used to do field service on a shipping container-sized desiccant wheel dehumidifier system sold to supermarkets. The wheel was about 5 feet wide, and there was a companion 5’ heat exchanger wheel. The pitch was that it would be more efficient and less expensive to run than using air conditioning to control humidity and frost buildup in the freezer section. They’re not around anymore, so I guess they couldn’t make it work.
The dessicant must be regenerated periodically. Either with very hot air or simple replacement. But if you remove moisture below 50% RH level, it is very uncomfortable.
@@janami-dharmam One side of the machine had a flow of hot air to dry out the wheel, the other had a flow of store air to be dried. The dessicant wheel turned slowly, picking up moisture on one half and being dried out on the other. The heat exchanger wheel turned more rapidly, and cooled the air back down (using air cooled by a swamp cooler) before it was dumped back in the store. The air would never get too dry because more-humid air from the other sections of the store, like produce, would mix in.
That desiccant drum has exactly the same honeycomb construction as a vehicle exhaust catalytic converter. We run a desiccant type downstairs in the living room & a compressor one upstairs. The desiccant one provides a little supplemental heat to the central heating during Winter with the living room doors closed & is reasonably quiet. In my experience the desiccant one runs a lot less than the compressor one for the same amount of water collected & with them both set to 50% RH.
Here in Houston, Texas, I have a compressor based one in the garage. Works great. There are only a few days a year that it gets cold enough for them not to work - and on those days, the humidity levels are low enough that the thing doesn't even turn on.
I would say mechanically they are more fussy, since there’s more moving parts and little things to go wrong, but a compressor based one is more complicated, if that makes sense. Also, to be fair the compressor based ones also put out a flow of warm air equal to whatever the machine wattage is, but they likely run less since they’re more efficient at removing the moisture.
I think they even can put out more heat than the electric power input because of the heat of condensation of water (2257 J/g). So for example if the amount of water it produces is 0,1g/s that is a 225.7 watt bonus :)
The compressor based ones put out approx 10% heat of the machine wattage. The desiccant ones put out a little more. In my experience, with a desiccant one downstairs (on it's lower setting of 300 watts) & a compressor one upstairs (190 watts) the desiccant one runs a whole lot less, whilst collecting the same amount of water as the compressor one.
Taking things to bits. It's my favorite pastime. I would make videos of it, but the most intelligent thing I can find to say about it is "Wow that's a lot of bits!" Then I throw the bits in the can, except for the shiny ones.
To make life easier. Instead of a stubby screw driver, drill holes in the bottom of he case so a regular screw driver can be used. Once the collection bin is in place no one will know they're there. Very handy if you plan to service it often.
The simplicity of this is very impressive. Thanks for taking it to bits! I wonder if there would be a way to use some gearing to ditch one of the motors? Could the zeolite drum be driven off the fan motor? That might cost too much in the engineering of the system and then, well, stuff does break. When I lived in Arizona they have a thing called a Swamp Cooler. It is basically a water reservoir at the bottom and a pump to raise the water up and drizzle it over a honey-comb type paper 'filter'. And then a fan (blower really, they kick out a lot of air!). It's mounted to your house, or whatever, and When it's very dry and hot, the device will force cooler wet air into your place. You need to pick one window far from the inlet and open it about 2-3 inches. That way, the incoming cold air will force the house air out that one exit, and fill your home with cool humid air! OK, so, it does happen that you get mosquitoes infesting the water reservoir of the swamp cooler (is that how it got the name?) and also, when the weather get's humid it doesn't work a damn. But when it does work, it is a joy. Similar simple design. Moving air and managing humidity. nice. I would like to get both of the installed in a 1 bedroom apartment and let the duel it out!
I think zeolite is also what's used in oxygen concentrators. From what i can gather, at a certain pressure, nitrogen gets absorbed into the zeolite, leaving behind air with a high level of oxygen in it which is sent to the output tube. The pressure is then released and the nitrogen leaves the zeolite and is vented to the ambient air. This happens over and over again and can actually give a decent flow of O2 gas. My brother had one at home when he needed medical oxygen, rather than have to have a replaceable tank.
I think zeolite is a bit of a generic name for a large group of minerals with these porous properties - I believe there's well over 200 discovered types in nature, but significantly more than that theoretically possible crystal arrangements that could have their own properties and maybe practical applications. i.e it's probably not the same material in the o2 application as in the dehumidifier.
I have done service on these! Large-capacity dessicant drier made by Munters, 480V 3ph. Dessicant wheel a little under 1m across. It is ducted with 10inch ducts to a larger walk-in environmental simulation chamber, approximately 150 cubic meters. It will take that chamber from 98%rh down to under 5%rh in 20 minutes! Great for humidity and temperature cycling tests, quickly removes moisture before the chamber ramps into subzero temperatures to avoid condensation settling and freezing onto test components.
I have never seen one of these in the states. I have one of the compressor based ones for that rare occasion when the weather gets weird and the basement gets damp. And those are dead common
I haven't ever heard of that device. I've seen plenty of compressor types, but this is the first time I've seen that passive magic material that collects the water. Will do some research on that right now!👍🤓 zeolite!?? Hmm
i have such dehumidifier and i love it. it is fairly silent and works great and is really efficient compared to the tec based systems but yea the compressor type are more effective and efficient as this system but cost more but save money in the long run. for a small budget dehumidifier i think the drum dehumidifier is the best. also if the room is already warm they tend to use less power. i have one who clams it would use 200W but uses in 25C only 30W to 60W depending if it is on a heating or cooling cycle. they need to cool down from time to time. i have tracked my humidity and temperature in my room over time and calculated the moisture content in the air and i saw as the temperature climbs the system goes more effective but it was clearly a step. this step was alway on the same time as the system uses less power and it tries to hold a certain temperature in the room. it was interesting to see the plots i made and this tells me how and when it works best but i did not know how it does this. now i know thanks ^^
Did testing with using a desiccant wheel with a standard compressor A/C to pull the water out to let the system just cool the air. Also did a liquid desiccant that pumped it over the hot roof to let the sun dry it out. Fun times.
I think these are easier to understand when you realise that they actually dehumidify using a room temperature condenser. For this to work they need to create hot humid air, and they do this using the combination of the desiccant to collect the water and the heater to circulate hot air over the wet desiccant. They're really intended for use in cold climates - they were invented by a Swede. Their main purpose in domestic use is usually to avoid mould occurring on the inside of outer walls due to condensation. The general consensus seems to be that they become more efficient (litres per kWh) than traditional refrigerated condenser dehumidifiers when operating at below around 20˚C at 60% humidity. This is usually the case in colder rooms overnight, which is where they're most needed. Also their quiet operation is a significant bonus overnight. It's worth pointing out that they contain a humidistat and so only run when required. I find that on the 300W setting mine runs at an average of under 100W, so that's roughly the same as an efficient fridge/freezer. Obviously in practice this depends on factors such as the number of people living in the house, the absolute humidity outside and how ventilated the house is. Most of the time in a UK winter the absolute humidity outside is lower than that inside, so the dehumidifier is really supplementing the ventilation. In theory the cost of running the dehumidifier is less than that of running more heating needed with increased ventilation.
These are a simplified version of the rotary concentrators used for pollution control with a thermal oxidizer. I am a field service engineer for an environmental company that builds and services this kind of equipment. Same idea as this design, except the purpose is to take high flow low VOC concentration air and concentrate it to low flow high concentration VOC air. This helps to make the oxidizer much smaller, as the oxidizer for the high flow low VOC air stream would need to be massive and consume huge amounts of natural gas. The VOCs in the air adsorb onto the wheel, then hot air that's heated by the oxidizer via a heat exchanger is blown across the wheel in a small pie section to desorb the VOCs off the wheel, which is then sent to the oxidizer. Typically two are used in series to achieve better efficiency. There's also usage of the VOC air as desorption air to increase efficiency as well.
I was meaning to make a video explaining how these work bit I think you've got it covered, so I won't bother. A reason they work so well in the cold is the colder the ambient air, the colder the plastic condenser will be so the better it will condense the moist air. One thing I would like to see is some sort of jogging method to knock droplets down off the inside condensor, to make more surface area for new condensation to form. I give mine a light kick or rock it about a bit, you can hear it dripping for a few seconds after. Another cool idea I had to improve efficiency, is use a peltier with heatpipes and a heatsink. The hot side being used to preheat the incoming moist air, and the cold side to be in contact with the condensor to make it colder to condense better.
It depends on the conditions. In hot and humid environments the compressor type dehumidifiers are better, but in colder, less humid conditions the dessicant type work better.
A friend of mine has a moisture issue in his house because the builder decided that putting a waterproofing membrane on the buried walls of and under the slab was for wimps. He basically runs compressor type dehumidifiers 24x7, and they're constantly pulling moisture from the air. I did suggest that this kind of desiccant dehumidifier might work better during winter, but I think he wasn't as interested since it wouldn't work during the hot Australian summer.
It you set it on top of the fridge so that the water output runs off into the evaporating dish on your fridge compressor, you'll never need to empty it. And Legionella will thank you
I tested a desiccant drum dehumidifier (Delonghi DNS65) against 2 simple compressor units. A 12 liter and a 16 liter. The 16l produced 9.5l in 24 hours and used 5.6kw/h The 12l produced 5.8l in 24 hours and used 5.5kw/h The DNS65 produced 5.3l in 24 hours and used 11.7kw/h In low noise mode 38db - 39db -34db they produced 0.32l - 0.24l - 0.14l in 2 hours and used 480w - 380w - 750w The desiccant drum dehumidifier is supposed to work best in low temperatures when the compressor models tend to ice up and need a defrost cycle. For normal room temperature the compressor models are the much more economic choice. The Delonghy had the loudest fan with 46db while the two compressors stayed around 41-42db. Thanks for taking it appart to give me a clearer idea how it works.
I've got a problem with mine. When the water in the tank gets to the point where it's full, as you mentioned in the video, there's float which rises and causes a magnet to be pulled away from a reed switch, prompting the electronics to shut down the machine and illuminate the tank full indicator LED. That has always worked fine until recently. What's started to happen is the tank gets full but the machine doesn't shut down as soon as it should, and eventually the tank overflows everywhere before it finally shuts off and leaves me with a puddle of water to deal with. I took the water tank apart and inspected the pivot between the float and the magnet in case it was getting gummed up with slime etc, and not moving freely, and it was indeed a bit messy so I cleaned all the parts thoroughly and put it back together. I thought that would have resolved the problem but it seems it hasn't. My theory is that over time the reeds inside the reed switch have become slightly magnetised, and as a result when the tank gets full and the magnet starts to pull away the reeds to not separate and the machine doesn't shut down. Is that possible? If so, I think just replacing the reed switch should do the job.
One of them dejavu moments, cos I re-watched your earlier vid on one of these just the other day and thought for some reason it was re-uploaded, neat to see one at its EOL though, I guess the bearings couldn't bear to go on... :P
Some prefer them for the lack of noise. Being in Asia summers are hot and humid so compressor works fine.. Winters are dry and cold so not needed here but they are still sold as they are quiet.. Zeolite I think is what many use
Mine cost 600$. And when I opened it up I saw that it was the small geared motor that had died. I ordered another from the Chinese jungle site, used an angle grinder to flatten one side of the pin and hey presto, thing has lot of years left 👍🙏😉
I remember taking one of these apart after a few years to clean it. The disc turned from brown to white on hoovering. It worked so much better, until a few months later it leaked all over the floor.
Thanks Clive. Dehumidifier helps tons with the Flood of moisture in air here (no AC) - except Heat it blows, in summer. Like said, Heat, during Cold would be nice, (no Heat here - but 'oil filled') tho i have Compressor type. Quiet would be nice, this 'Buzzes', could be Case not 'tight' enough [?] lol i tried to find, Water in tub muffles it some. Seems i need to move to other areas more often, maybe I'm slowing down. oh Jeez! : } cheers!
The perfect use for those dryers is for curing meats (Salami proschiutto,sausages )And drying peppers and herbs of various varieties ,like hemp ,teas or rosemary and other important flavourings in your cold cellar .if you have one .alot quieter than compressor powered devices .but whatever helps to dry your room it's important
It's a very common style of motor. The ones in microwaves usually have no specific direction, so the turntable will rotate in a random direction when started.
I had a similar one. It was quite effective but I didn't like the smell it gave out. The same desiccant disc motor failed on mine and plastic parts near the heater melted. They are much more cheaply made than the compressor type and I wouldn't get one again.
Just fell over this one this morning - !! - that's ow it works? Great! pity about the slime blockages. Just done a kwik search.. seems like this is in all those "Cheaper" dehumidifiers for sale... Nope NOT all .. have to check out the specs or look in the box first. Doesn't Corries just like me coming in! ;-) Spot on, man!
Wonder if calcium chloride works as well as corrugated cardboard & if sunlight can dry it as well as a heating element. It could be a solar powered desiccant food dehydrator.
wonder how hard it would be to combine this with a vortex tube to make it 100% air powered use the cold output of the vortex tube to condense water that is blown through the desiccant, even as far as having it blow into itself , im going to have to keep an eye out for 1 of these at goodwill
Thanks for this. I tried to repair an ecoair dd322fw classic, after this and the other video. The unit was "working" but was not collecting water. There is no plastic condenser behind the dessicant coil. I tried another dd322fw which did collect water. Did they not have these condensers in earlier models? I tried another dd322fw which did collect water, lots of it!
I used to repair these and they were a nightmare, not exactly reliable, the dessicant wheels used to go mouldy and absolutely stink, the regen and dessicant wheel motors used to fail with monotonous regularity. They tended to overheat a lot too.
Was it a Bry-Air? That described our experience exactly: we had a 1200 CFM unit for a lab that ate 20 kW, and it worked maybe 1/4 of the time. From what I understood, it was like you said: motor failure, and the thing would regularly overheat and trip off.
If the system was kept clean, or redesigned a bit, shouldn't the water be safe to drink as it's heated to a hot vapor? The heating element gets hot enough to char the desiccant wheel. I bought one of these and took it apart immediately after the first hour of use as it had a slight burned smell. The whole wheel was slightly browned from the heating. I didn't measure the temp but I assume the air is heated enough to kill any bacteria or spores that may be lingering? My desiccant unit holding tank water stays crystal clear, even after sitting for a few weeks as I've forgotten about it. That's the problem with a compressor unit, the cold, wet evaporator coil is a good air filter and traps bacteria and spores in the water as it drips down the collector pan.
My AEG AC unit can dehumidify 5 liters in 4 hours. It's so surreal to empty a bucket of water into the toilet every 4 hrs. Our summers in Germany are extremely humid and increasingly hot, which makes the air able to even store more humidity... Spanish plumes for 6+ months keep us nice and toasty. The landscape changes to a desert.
I've heard of these but am not sure I've seen them for sale in my area. I assume they're not very common in the US as compressor based models generally make more sense - the advantage of operating down to cold ambient temps really just doesn't matter outside of particular climates. Here in the Midwest our humidity levels in winter plummet, and I joke that the humidity here is consistently wrong - dehumidifiers in the summer, humidifiers in the winter! Right now is one of the few times of the year where I'm not bothering to fiddle with it.
I would like to get a hold of one of thse and do some energy consumption comparisons. I like the idea of something quieter, but then again (and this might also have something to do with them apparently being rare here) I have a dehumidifier in the basement and use the HVAC fan to move air throughout the building. Since that's almost a given feature in US homes, we tend to like big, powerful units and put them somewhere the noise isn't a problem. Plus, air conditioning does its own moisture removal, too.
I've used similar units in the US for industrial type uses where complete control of the air temp and humidity is required. Ie clean room environments.
Whatcha Techno Boy ! love your work...cheers.
I live in MN and have one of these. There's an "Ivation" brand one for sale on Amazon. I actually use it in the garage in the winter time. I keep it lightly heated (~40F or so) and all the snow that drops off the car creates a ton of moisture in the garage that condenses everywhere. This works really well in those cold temps where a compressor based one will not operate, and as a bonus provides a little bit of heat to the garage.
I bought one on amazon for not too much money. I use it in the basement during the winter when the compressor dehumidifier stops working because it gets too cold down there.
@@andrewt9204 Good use case
This is such a clever little device! I love how it’s basically a heater that makes water from the air. I wonder if I could use a modified design for project Chickenhole. Perhaps concentrated sunlight instead of electricity?
Since a compressor dehumidifier is just an AC running in a closed room, the simplest solution should be a peltier "cooler" (fans optional). For efficiency it will be hard to beat a compressor, so that leaves this device as a neat in-between for both complexity and power usage?
Hey Cody 🙂
Hi Cody
hey cody, glad to see you following 1 of the best teardown channels on youtube :)
also instead of direct solar, why not run a 30 watt panel to a pc fan and however much nichrome it can handle?
Requires humidity in the air for it to operate. Using direct solar heating is interesting but still not much water there to collect. Chickenhole looks pretty arid.
TLDR: the difference between Can and Should.
There is at least one company using this desiccant+heat process to market a magic "water from air" product. The irony of all such products is that they only work in humid environments.
My patented invention produces water for free but only if installed near a lake.
Counterpoint: while those are obviously quack products, with global warming disrupting cloud formation, drought is becoming increasingly common in the Great Plains. Quite a lot of humid air simply floats over without condensing into rain. Condensing water on an industrial scale might become a necessity within my lifetime at this rate.
@@demef758 Can I interest you in the Peckham Spring Water company?
@@cheyannei5983 The heat of transformation needed to condense liquid frm vapor is exactly the same as the power used to boil that same amount of water. Consider the amount of water condensed by an air conditioner. It does make measurable liquid, but the energy cost per gallon is horrendous.
Could it be done on an industrial scale? Yes, but you couldn't afford the water produced that way.
@@cheyannei5983 OK, doomer.
Zeolite can also be used for VOC extraction from air. Industrial VOC versions of the zeolite disc in this basic arrangement are commonly 3 meters dia by 50-100cm depth. The adsorption (gas phase to liquid phase) process concentrates VOCs from the air stream and are cleverly called rotary concentraters in the air pollution control industry. The captured and concentrated VOCs are commonly fed into a gas fired burner that provides the heat energy necessary for the heated desorption loop making them rather efficient.
My English isn't very good, so I'm not sure if I understand correctly. Do the VOCs condense in the water taken from the air and are then burned at the end (so the zeolite is clean from VOCs)?
I asked Bard: she says
[you are ] describing a process called rotary zeolite adsorption for VOC extraction from air. This process uses a large rotating wheel (disc) made of zeolite, a porous material that can adsorb VOC molecules.
The process works as follows:
The air to be treated is passed through the zeolite wheel. The VOC molecules in the air are adsorbed by the zeolite, while the clean air exits the wheel.
The zeolite wheel is then rotated to the desorption section. In this section, a hot gas stream is passed through the zeolite wheel, causing the VOC molecules to desorb from the zeolite and into the hot gas stream.
The hot gas stream containing the concentrated VOCs is then passed to a thermal oxidizer, where the VOCs are destroyed.
The zeolite wheel is then rotated back to the adsorption section, and the process starts again.
This process is very efficient for VOC extraction from air, because it can concentrate the VOCs into a small volume of gas, which makes it easier and more efficient to destroy the VOCs in the thermal oxidizer.
So, to answer your question, the VOCs are not condensed in the water taken from the air. Instead, they are concentrated in a hot gas stream and then destroyed in a thermal oxidizer.
This process is a very effective way to remove VOCs from air emissions from industrial facilities. It is widely used in a variety of industries, including automotive manufacturing, printing, and electronics.
TOP TIP for Meaco DD8 (possibly the model in the video) to lessen sludge-formation in the area Clive showed: after removing the bucket, tilt the dehumidifer over onto its righthand side (looking at from the bucket side). This will drain the silly little sump over toward the hole that drains into the bucket.
(BONUS, if you happen to own an Ecoair DD1, which isn't the model in the video):
For preventing sludge building up in a similar way: after removing the bucket, tilt up the dehumidifier toward the closed short edge (the end opposite where the bucket aperture is) and slightly to the left as you look down into the bucket-hole. This will overflow the collected water from where it collects and allow it to drain over the plastic plate above where the bucket goes; you'll see a stream of water trickling down to that now bottom corner. Jiggle the unit as you tilt it to maximise drainage. I soak up this water with a cloth and repeat until the stream stops. It is always a surprising amount.
Edit: just to say, desiccant dehumidifiers are absolutely the way forward for clothes-drying indoors in damp winters. They may seemingly use a lot of energy, but their 'waste' product is heat, which nicely warms the room they're used in.
Also, GREAT video, Clive!
Bought one of this type four of five years ago after I saw a previous video of yours on one and it still works great for drying clothes gently here in wet-ish Seattle. Maybe time to open mine up and see how bad it is on the slime front... Thanks for the reminder Clive!
I thought he'd taken apart one of these before. Thank you for making me feel less crazy.
@@IceBergGeo ruclips.net/video/mR57FhytzFk/видео.html Found the video!
warmth + humidity = happiness.
What a fascinating device.
Never knew they existed, let alone how they work.
I learn something new with every one of your videos.
Interesting. Never seen one of these as an ambient air dehumidifier, though, I’ve worked on quite a few that are compressed air dryers. Look up Atlas Copco’s MD Dryer operation. Same principle, but uses heat of compression from an oil free compressor (typically 75kw/100hp and up) for the regeneration process. When sized correctly, it’s an efficient way to dry the air and usually better (lower dew point) than a refrigerated dryer can achieve. Thanks for sharing
Thanks for telling us this info ... we use hydrovanes without dehumidifiers - but on look out for one .... need to do some research here. Slàinte Mhath.
If you heat a mass of cold air, you automatically dehumidify it. The actual amount of water vapor remains the same, but the RH value which is the direct measure of humidity decreases. However, if you cool a given mass of warm air, you must remove excess water because the air becomes saturated with water very quickly if you cool it.
I don't get, why nobody combines it for a household dehumidifier. Is it too expensive to sell or too big?
@@CyberlightFG all the moisture is trapped by the gel but the gel must be dehumidified periodically. That step is not done well. Without that it won't work well.
@@janami-dharmam Preheat it with the warm air from the refrigeration system
I got the same make dehumidifier you have and it works great.Handy to see the bits inside and where the sludge build up is going to be.
Where I work we have several very large versions of this. The drums are about 6 foot in diameter. Got to see one of the drums get replaced due to 20 years or so of usage. It had been eaten away pretty badly and was very clogged. Still a very good and simple tech for what it does.
We call them Kyotowheels. Green Datacenter use them. Also saw them in Make-up air units
I have 2 of these ... solved all my winter mould problems ... just brilliant ... buy a meter that shows humidity once the house gets down to 45% no point running them any longer ...
I'm from the high deserts of Colorado, and we have low humidity year-round. My first work trip sent me to Texas / Louisiana border next to the Golf Coast, and the hotel room had a loud dehumidifier. After talking with my Sister, who lived in Texas and Florida, she said everyone just ran the AC all the time. Clive had a dehumidifier video out at the same time talking about warming up the room some to have better results. I raised the room temp, and the dehumidifier quieted down, and in one night, it pulled about a gallon of water out of the air in the hotel room. I also remember going out at 6:30. The sun was starting to come up, and it was already hot, and I felt like the air was so thick it was suffocating me. I was glad to return to the dry air from home, where we cool the air with swamp coolers, evaporating water over shaved aspen pads.
I have 2 of each type. Had to replace several dodgy motor caps in the Delonghi compressor type. Another problem is the humidity sensors, probably due to a buildup of fluff around them. In general though I do prefer the desiccant dehumidifiers as they're quieter and have better air filtration and the ones we have incorporate a timer for 2,4 and 8 hours of operation. Regardless of the type it is remarkable how much water they can pull out of the air in a sealed room.
One other tip, these are great for drying clothes.
One thing about desiccant drums is that they are more scalable. We use one to dry ambient air before it goes in to a large reactor building. Of course it helps have a fixed unit and can separate the air path for the hot, humid air.
im a hvac tech really enjoyed this and always wondered how these work all though ive only ever seen a couple on site but good to know they are a alternitive in cool enviroments where evaporator coils dont dehumidifie well.
When my wife was at the end of her life, she used a zeolite-based home oxygen concentrator that worked in a similar way. Instead of using heat to drive out the humidity, it had two zeolite-filled pressure cylinders which were alternately pumped up to 2.5 atm to get the zeolite honeycomb to absorb nitrogen. The pressure was then released and the nitrogen-poor (and oxygen-rich) air was pumped through a face mask. It would then switch the cycle to the other cylinder and let the first cylinder return to atmospheric pressure, releasing its stored nitrogen and ready to start the cycle again.
this is the idea used in common oxygen concentrators used in hospitals. They were in great demand during the Covid pandemic. But the actual zeolite used appears to be a trade secret.
My grandfather has a machine by his bed that sound exactly like what you're describing - I think it helped with sleep apnoea near the end of his life. I never knew how it worked! Thanks so much for sharing your knowledge.
I've been tempted to buy one to explore.
At the peak of the pandemic, India began to run short of oxygen for medical use. So there was a crash government programme to make more zeolite oxygen concentrators. Here a video on the operating principles of the two-cylinder type, used for both domestic and hospital units ruclips.net/video/AE5QOq-HN3U/видео.html
Fascinating. I've not seen one of these before as it's fairly dry where I live. Thanks Clive.
Thanks Clive! This helped me fix my desiccant dehumidifier. It had started to make strange noises and one day all the washing it was drying was covered in what turned out to be tiny mica flakes. The sump had blocked with slime as you suggested and the hot air blower fan had been paddling through the water. Some water had been flung up into the heating element and that needed drying with a hot air gun and also blowing out all the loose mica flakes. Unfortunately my model did need to be disassembled to get access to the sump to clean it out.
Simple they may be, but for the significant amount of cable spaghetti inside with all those sensors; not easy to disconnect all the bits that needed to come out, but it is working fine again now.
Ok WOW now I get it! There's two air paths. Never heard that most important detail before now... no idea why, seriously! So thanks!
Taking things to bits, is a good philosophy to live by.
I've worked on scaled-up versions of this at ice hockey arenas with 3 million BTU/Hr burners to supply the heat to dry the desiccant.
I'd say that the compressor based dehumidifiers have the downside of more noise, and you also have refrigerant that can leak. But these desiccant based ones seem to require much more monitoring and maintenance if you want them to last.
I always enjoy your very knowledgeable insights on electronics and gadgets, I've been spending a lot of time for my other hobbies like art and making ramen completely from scratch.
I'm a "big fan" of these kinds of tear down videos!
Thank you for the video on Dessicant air dryer adsorption moisture zeolite cold air honeycomb mesh absorber home quiet household dehumidifier machine.
I've got storage in a unheated building. I put a very big bucket with road salt in. (Mesh bucket with salt in a coffee bag over a construction bucket underneath.) Thats effective and very cheap. But that's still not enough to keep it dry.
Some people overfill it and it makes a huge mess of saltwater.
Always wondered, but now I know how these quiet dehumidifiers work. Thanks Clive!
Neat! Heard about these units but never seen one before today! Thanks!
Live on the west coast of Canada and only run the dehumidifier in the winter. Helps heat the room and as a bonus drops the humidity levels and keeps the windows drier on the inside.
I once had to change a 9ft diameter desiccant drum at a plastic factory in Banbury. It used Gas burners as electric heaters weren't powerful enough. It was made by a company called Munters.
The guided tour I never knew I needed, interesting for sure!
Liking your analysis of physical things.
I've got a similar one bought on Amazon UK three years ago. Called "Ecoair DD1 simple desiccant dehumidifier", it cost 130ukp at the time. It's been very good. Though it's made in China it is ideally suited to the British climate in winter, that is damp cold air. I also live by the sea, adding to the humidity, and in a mid Victorian solid brick home which tends to get damp in winter. The Ecoair's stated operating range is 1 degree C to 35 degrees C. I also bought a Thermopro digital hygrometer at the same time. This measures air dampness accurately, so I can turn on the dehumidifier if relative humidity inside strays too high. The dehumidifier is also helpful if you are trying to dry clothes indoors, speeding things up considerably.
However, it would not be suitable for a hot humid climate, as the Zeolite-based drying process heats the air. And in places with cold dry winters you're unlikely to need one, as you could probably get rid of internal condensation simply by better ventilation.
UPDATE: just found a Big Clive video from two years ago taking this exact Ecoair model apart ruclips.net/video/BUJqUapiNEc/видео.html. It also goes into the interesting Zeolite desiccant air drying process some more, and the kind of things that can go wrong. But basically the Ecoair seems to be a cost effective, durable device if you live in the type of climate (cold, damp) where dessicant dehumidifiers beat the more widely available refrigerator-like compressor type (better in hot damp conditions).
EBay version: low power saving dehumidifier magic fan heater safe uk plug. Features: 240v case, no earthing, only uses 5w, low power no heating element, magic fan, available colours blue, pink, black, random (colour may be different due to monitor) only available in green.
I live in an area where humidifiers and dehumidifiers are not really necessary (aside from maybe a handful of days every year) so I don’t think I’ve ever seen one of these before. I have a portable AC unit which has a dehumidifier function that I use occasionally during the short periods we have where it is mild temperatures and very humid.
I have had 2 dehumidifiers, the first was a desiccant and the latest is a compressor. In use the desiccant pulled out moisture much quicker than the compressor, although I haven’t checked the comparative energy use per litre...
My wife had an amazing idea earlier this year. We bought a dehumidifier to help us deal with some air conditioning issues over summer. We normally use distilled water in our humidifiers over wintertime, so we don't have to contend with calcium scale (our water is fairly hard). So... put the condensate from the dehumidifier in the distiller, and store it for the wintertime. Obviously, while all stages of this use electrical power, it's nothing we wouldn't be running anyway, and I'd bet it cuts down our tap water use a bit. Never hurts having drinkable water on standby either.
Just be aware that distilled water from AC condensate is considered corrosive, it can eat away copper or aluminum. I don't know what makes it so, but check the pH before drinking or putting it into the humidifier!
Condensate from condensing heating boilers is acidic. I just tested the water from my desiccant drum dehumidifier and it was a neutral value of 7.
I fixed one of these recently, where the regeneration fan motor bearings had stopped working properly. They are quite odd -- they hadn't worn out, but the self-alignment spring was a bit loose causing the actual bearing to wobble around.
It looks a lot easier to get apart if you lop all the wires off first!
Yeah. They have quite a wiring loom in them.
This is exactly the answer to what i was wondering 2 days ago! Thanks
Ah, temperature swing adsorption dehumidification. Used extensively in large volume dehumidification like hockey rinks. The efficiency scales down too so these small room units are quite useful.
Condensing surfaces grow slime with the cleanest air since bacteria only need water and a carbon source. With that warmth, several pathogens are possible including Legionella.
The smaller blower motor is the typical shielded pole motor, I know it well as my 4 l water distiller uses a near identical copy. I've relubricated its bearings yearly for the past 10 years. From it, I get distilled water at pennies a liter and free, gentle heat for the bathroom. Far easier to clean the distiller than the water kettle, coffee maker and steam iron.
@@Bobo-ox7fj
It is 20+ years old. I've seen the same design sold through Amazon. It was given to me.
I used to do field service on a shipping container-sized desiccant wheel dehumidifier system sold to supermarkets. The wheel was about 5 feet wide, and there was a companion 5’ heat exchanger wheel.
The pitch was that it would be more efficient and less expensive to run than using air conditioning to control humidity and frost buildup in the freezer section.
They’re not around anymore, so I guess they couldn’t make it work.
The dessicant must be regenerated periodically. Either with very hot air or simple replacement. But if you remove moisture below 50% RH level, it is very uncomfortable.
@@janami-dharmam One side of the machine had a flow of hot air to dry out the wheel, the other had a flow of store air to be dried. The dessicant wheel turned slowly, picking up moisture on one half and being dried out on the other. The heat exchanger wheel turned more rapidly, and cooled the air back down (using air cooled by a swamp cooler) before it was dumped back in the store.
The air would never get too dry because more-humid air from the other sections of the store, like produce, would mix in.
Thanks for another great video 👋
I hope everyone is well and doing ok
That desiccant drum has exactly the same honeycomb construction as a vehicle exhaust catalytic converter. We run a desiccant type downstairs in the living room & a compressor one upstairs. The desiccant one provides a little supplemental heat to the central heating during Winter with the living room doors closed & is reasonably quiet. In my experience the desiccant one runs a lot less than the compressor one for the same amount of water collected & with them both set to 50% RH.
Here in Houston, Texas, I have a compressor based one in the garage. Works great. There are only a few days a year that it gets cold enough for them not to work - and on those days, the humidity levels are low enough that the thing doesn't even turn on.
Fascinating Clive never seen one of them before thanks
I would say mechanically they are more fussy, since there’s more moving parts and little things to go wrong, but a compressor based one is more complicated, if that makes sense. Also, to be fair the compressor based ones also put out a flow of warm air equal to whatever the machine wattage is, but they likely run less since they’re more efficient at removing the moisture.
I think they even can put out more heat than the electric power input because of the heat of condensation of water (2257 J/g). So for example if the amount of water it produces is 0,1g/s that is a 225.7 watt bonus :)
The compressor based ones put out approx 10% heat of the machine wattage. The desiccant ones put out a little more. In my experience, with a desiccant one downstairs (on it's lower setting of 300 watts) & a compressor one upstairs (190 watts) the desiccant one runs a whole lot less, whilst collecting the same amount of water as the compressor one.
Protip if you can't fit a screwdriver in tight quarters, you can try fitting a 1/4" screwdriver bit onto a 1/4" spanner or ratchet socket.
had to look. but you have tore these apart several times and its cool to see not much has changed in their designs.
Cool stuff, never seen one of these before. Every day is a skool day with big C.
Thank you that's something novel and interesting to me, very simple
Taking things to bits. It's my favorite pastime. I would make videos of it, but the most intelligent thing I can find to say about it is "Wow that's a lot of bits!" Then I throw the bits in the can, except for the shiny ones.
To make life easier. Instead of a stubby screw driver, drill holes in the bottom of he case so a regular screw driver can be used. Once the collection bin is in place no one will know they're there. Very handy if you plan to service it often.
Good idea
The simplicity of this is very impressive. Thanks for taking it to bits! I wonder if there would be a way to use some gearing to ditch one of the motors? Could the zeolite drum be driven off the fan motor? That might cost too much in the engineering of the system and then, well, stuff does break. When I lived in Arizona they have a thing called a Swamp Cooler. It is basically a water reservoir at the bottom and a pump to raise the water up and drizzle it over a honey-comb type paper 'filter'. And then a fan (blower really, they kick out a lot of air!). It's mounted to your house, or whatever, and When it's very dry and hot, the device will force cooler wet air into your place. You need to pick one window far from the inlet and open it about 2-3 inches. That way, the incoming cold air will force the house air out that one exit, and fill your home with cool humid air! OK, so, it does happen that you get mosquitoes infesting the water reservoir of the swamp cooler (is that how it got the name?) and also, when the weather get's humid it doesn't work a damn. But when it does work, it is a joy. Similar simple design. Moving air and managing humidity. nice. I would like to get both of the installed in a 1 bedroom apartment and let the duel it out!
De-humidification has become mandatory in Central Europe. The hot summers are not only hot, but very humid as well.
That looked like fun. Reassemble it and use one of those mini stepper motors to turn the drum. Good luck! 👍
I think zeolite is also what's used in oxygen concentrators. From what i can gather, at a certain pressure, nitrogen gets absorbed into the zeolite, leaving behind air with a high level of oxygen in it which is sent to the output tube. The pressure is then released and the nitrogen leaves the zeolite and is vented to the ambient air. This happens over and over again and can actually give a decent flow of O2 gas. My brother had one at home when he needed medical oxygen, rather than have to have a replaceable tank.
I think zeolite is a bit of a generic name for a large group of minerals with these porous properties - I believe there's well over 200 discovered types in nature, but significantly more than that theoretically possible crystal arrangements that could have their own properties and maybe practical applications. i.e it's probably not the same material in the o2 application as in the dehumidifier.
I have done service on these! Large-capacity dessicant drier made by Munters, 480V 3ph. Dessicant wheel a little under 1m across. It is ducted with 10inch ducts to a larger walk-in environmental simulation chamber, approximately 150 cubic meters. It will take that chamber from 98%rh down to under 5%rh in 20 minutes!
Great for humidity and temperature cycling tests, quickly removes moisture before the chamber ramps into subzero temperatures to avoid condensation settling and freezing onto test components.
I would suggest getting the replacement motor and grinding or filing the two flat sides on the shaft to make it match the original one.
I have never seen one of these in the states. I have one of the compressor based ones for that rare occasion when the weather gets weird and the basement gets damp. And those are dead common
I haven't ever heard of that device. I've seen plenty of compressor types, but this is the first time I've seen that passive magic material that collects the water. Will do some research on that right now!👍🤓 zeolite!?? Hmm
i have such dehumidifier and i love it. it is fairly silent and works great and is really efficient compared to the tec based systems but yea the compressor type are more effective and efficient as this system but cost more but save money in the long run. for a small budget dehumidifier i think the drum dehumidifier is the best. also if the room is already warm they tend to use less power. i have one who clams it would use 200W but uses in 25C only 30W to 60W depending if it is on a heating or cooling cycle. they need to cool down from time to time. i have tracked my humidity and temperature in my room over time and calculated the moisture content in the air and i saw as the temperature climbs the system goes more effective but it was clearly a step. this step was alway on the same time as the system uses less power and it tries to hold a certain temperature in the room.
it was interesting to see the plots i made and this tells me how and when it works best but i did not know how it does this. now i know thanks ^^
Did testing with using a desiccant wheel with a standard compressor A/C to pull the water out to let the system just cool the air. Also did a liquid desiccant that pumped it over the hot roof to let the sun dry it out. Fun times.
I think these are easier to understand when you realise that they actually dehumidify using a room temperature condenser. For this to work they need to create hot humid air, and they do this using the combination of the desiccant to collect the water and the heater to circulate hot air over the wet desiccant.
They're really intended for use in cold climates - they were invented by a Swede. Their main purpose in domestic use is usually to avoid mould occurring on the inside of outer walls due to condensation. The general consensus seems to be that they become more efficient (litres per kWh) than traditional refrigerated condenser dehumidifiers when operating at below around 20˚C at 60% humidity. This is usually the case in colder rooms overnight, which is where they're most needed. Also their quiet operation is a significant bonus overnight.
It's worth pointing out that they contain a humidistat and so only run when required. I find that on the 300W setting mine runs at an average of under 100W, so that's roughly the same as an efficient fridge/freezer. Obviously in practice this depends on factors such as the number of people living in the house, the absolute humidity outside and how ventilated the house is. Most of the time in a UK winter the absolute humidity outside is lower than that inside, so the dehumidifier is really supplementing the ventilation. In theory the cost of running the dehumidifier is less than that of running more heating needed with increased ventilation.
These are a simplified version of the rotary concentrators used for pollution control with a thermal oxidizer. I am a field service engineer for an environmental company that builds and services this kind of equipment. Same idea as this design, except the purpose is to take high flow low VOC concentration air and concentrate it to low flow high concentration VOC air. This helps to make the oxidizer much smaller, as the oxidizer for the high flow low VOC air stream would need to be massive and consume huge amounts of natural gas. The VOCs in the air adsorb onto the wheel, then hot air that's heated by the oxidizer via a heat exchanger is blown across the wheel in a small pie section to desorb the VOCs off the wheel, which is then sent to the oxidizer.
Typically two are used in series to achieve better efficiency. There's also usage of the VOC air as desorption air to increase efficiency as well.
I was meaning to make a video explaining how these work bit I think you've got it covered, so I won't bother.
A reason they work so well in the cold is the colder the ambient air, the colder the plastic condenser will be so the better it will condense the moist air.
One thing I would like to see is some sort of jogging method to knock droplets down off the inside condensor, to make more surface area for new condensation to form.
I give mine a light kick or rock it about a bit, you can hear it dripping for a few seconds after.
Another cool idea I had to improve efficiency, is use a peltier with heatpipes and a heatsink. The hot side being used to preheat the incoming moist air, and the cold side to be in contact with the condensor to make it colder to condense better.
I'd be real curious to use an equal powered compressor unit side by side and see which one can collect more water for the power used.
It depends on the conditions. In hot and humid environments the compressor type dehumidifiers are better, but in colder, less humid conditions the dessicant type work better.
@@DrAHorn here it's warm and humid, Hawaii. So I enjoy the cool air the compressor model creates.
A friend of mine has a moisture issue in his house because the builder decided that putting a waterproofing membrane on the buried walls of and under the slab was for wimps. He basically runs compressor type dehumidifiers 24x7, and they're constantly pulling moisture from the air. I did suggest that this kind of desiccant dehumidifier might work better during winter, but I think he wasn't as interested since it wouldn't work during the hot Australian summer.
The answer is to use compressor in the hot season and desiccant in the cold season.
Compressor based dehumidifiers don't seem to be particularly loud. I found that, at least on my meaco unit, it's mostly fan noise.
Very informative thanks Clive.
It you set it on top of the fridge so that the water output runs off into the evaporating dish on your fridge compressor, you'll never need to empty it.
And Legionella will thank you
You don't realize that if you do that your putting the moisture back into the air?
I tested a desiccant drum dehumidifier (Delonghi DNS65) against 2 simple compressor units. A 12 liter and a 16 liter.
The 16l produced 9.5l in 24 hours and used 5.6kw/h
The 12l produced 5.8l in 24 hours and used 5.5kw/h
The DNS65 produced 5.3l in 24 hours and used 11.7kw/h
In low noise mode 38db - 39db -34db they produced 0.32l - 0.24l - 0.14l in 2 hours and used 480w - 380w - 750w
The desiccant drum dehumidifier is supposed to work best in low temperatures when the compressor models tend to ice up and need a defrost cycle.
For normal room temperature the compressor models are the much more economic choice.
The Delonghy had the loudest fan with 46db while the two compressors stayed around 41-42db.
Thanks for taking it appart to give me a clearer idea how it works.
I've got a problem with mine. When the water in the tank gets to the point where it's full, as you mentioned in the video, there's float which rises and causes a magnet to be pulled away from a reed switch, prompting the electronics to shut down the machine and illuminate the tank full indicator LED. That has always worked fine until recently. What's started to happen is the tank gets full but the machine doesn't shut down as soon as it should, and eventually the tank overflows everywhere before it finally shuts off and leaves me with a puddle of water to deal with. I took the water tank apart and inspected the pivot between the float and the magnet in case it was getting gummed up with slime etc, and not moving freely, and it was indeed a bit messy so I cleaned all the parts thoroughly and put it back together. I thought that would have resolved the problem but it seems it hasn't. My theory is that over time the reeds inside the reed switch have become slightly magnetised, and as a result when the tank gets full and the magnet starts to pull away the reeds to not separate and the machine doesn't shut down. Is that possible? If so, I think just replacing the reed switch should do the job.
Does the machine stop when the water collection tray is pulled out? That would indicate if the reed switch was sticking.
One of them dejavu moments, cos I re-watched your earlier vid on one of these just the other day and thought for some reason it was re-uploaded, neat to see one at its EOL though, I guess the bearings couldn't bear to go on... :P
Some prefer them for the lack of noise. Being in Asia summers are hot and humid so compressor works fine.. Winters are dry and cold so not needed here but they are still sold as they are quiet.. Zeolite I think is what many use
Rather cool device I’ve only seen compressor ones where I’m from in the states
If the fan is stalled and you can push start it, it's the capacitor.
Very cool to watch...Thanks DVD:)
Mine cost 600$. And when I opened it up I saw that it was the small geared motor that had died. I ordered another from the Chinese jungle site, used an angle grinder to flatten one side of the pin and hey presto, thing has lot of years left 👍🙏😉
Our heat pump type puts out quite a stream of warm air too.
Rehearsal is for Tattoos. Off the knitted cuff is best for suspense and entertainment in docu-dramas. Interesting and informative, as ever.
I remember taking one of these apart after a few years to clean it. The disc turned from brown to white on hoovering. It worked so much better, until a few months later it leaked all over the floor.
The leaking is a common issue when they gunk up inside.
Thanks Clive. Dehumidifier helps tons with the Flood of moisture in air here (no AC) - except Heat it blows, in summer.
Like said, Heat, during Cold would be nice, (no Heat here - but 'oil filled') tho i have Compressor type.
Quiet would be nice, this 'Buzzes', could be Case not 'tight' enough [?] lol i tried to find, Water in tub muffles it some.
Seems i need to move to other areas more often, maybe I'm slowing down. oh Jeez! : } cheers!
I think the dehumidifier my friends got is of the compressor verity, it's got a big lump at the bottom.
Works well for a little noisy bugger! 😆👍
can you open up a smart Gas Valve preferably Honeywell ones and explain how it functions and talk about possible failures and causes....
A cool teardown of an Interesting device :)
I work at a place with 2 ice hockey rinks. Both have giant desiccant drum dehumidifiers. Massively large units compared to this one.
The perfect use for those dryers is for curing meats (Salami proschiutto,sausages )And drying peppers and herbs of various varieties ,like hemp ,teas or rosemary and other important flavourings in your cold cellar .if you have one .alot quieter than compressor powered devices .but whatever helps to dry your room it's important
I still need to replace the faulty drum motor in mine, the replacement motor has been sat on top of it for nearly a year...
Where did you get the motor? I couldn't find one with matching shaft flats.
@@bigclivedotcom RUclips won't let me tell you.
Uploaded 16 minutes ago... I don't think I've ever been this early to a Big Clive video!
Cool device, that smaller motor looks almost identical to the rotating plate motors used in microwaves,
It's a very common style of motor. The ones in microwaves usually have no specific direction, so the turntable will rotate in a random direction when started.
I had a similar one. It was quite effective but I didn't like the smell it gave out. The same desiccant disc motor failed on mine and plastic parts near the heater melted. They are much more cheaply made than the compressor type and I wouldn't get one again.
Just fell over this one this morning - !! - that's ow it works? Great! pity about the slime blockages. Just done a kwik search.. seems like this is in all those "Cheaper" dehumidifiers for sale... Nope NOT all .. have to check out the specs or look in the box first. Doesn't Corries just like me coming in! ;-) Spot on, man!
Wonder if calcium chloride works as well as corrugated cardboard & if sunlight can dry it as well as a heating element. It could be a solar powered desiccant food dehydrator.
Calcium chloride is a wet desiccant.
Which device is it (or more precisely which device do you recommend, for efficiency, and ideally easy to repair)?
wonder how hard it would be to combine this with a vortex tube to make it 100% air powered
use the cold output of the vortex tube to condense water that is blown through the desiccant, even as far as having it blow into itself , im going to have to keep an eye out for 1 of these at goodwill
Thanks for this. I tried to repair an ecoair dd322fw classic, after this and the other video.
The unit was "working" but was not collecting water.
There is no plastic condenser behind the dessicant coil. I tried another dd322fw which did collect water.
Did they not have these condensers in earlier models?
I tried another dd322fw which did collect water, lots of it!
I've always known them to have condensers. I wonder if someone has removed it.
I used to repair these and they were a nightmare, not exactly reliable, the dessicant wheels used to go mouldy and absolutely stink, the regen and dessicant wheel motors used to fail with monotonous regularity. They tended to overheat a lot too.
Was it a Bry-Air? That described our experience exactly: we had a 1200 CFM unit for a lab that ate 20 kW, and it worked maybe 1/4 of the time. From what I understood, it was like you said: motor failure, and the thing would regularly overheat and trip off.
@@straightpipediesel No, these were for domestic use but still got abuse by builders etc.
I think the technology is still in its infancy for home use.
If the system was kept clean, or redesigned a bit, shouldn't the water be safe to drink as it's heated to a hot vapor? The heating element gets hot enough to char the desiccant wheel. I bought one of these and took it apart immediately after the first hour of use as it had a slight burned smell. The whole wheel was slightly browned from the heating. I didn't measure the temp but I assume the air is heated enough to kill any bacteria or spores that may be lingering? My desiccant unit holding tank water stays crystal clear, even after sitting for a few weeks as I've forgotten about it.
That's the problem with a compressor unit, the cold, wet evaporator coil is a good air filter and traps bacteria and spores in the water as it drips down the collector pan.
I'd probably drink it in an emergency, but only after treating it further by boiling or adding trace chlorine.
My AEG AC unit can dehumidify 5 liters in 4 hours. It's so surreal to empty a bucket of water into the toilet every 4 hrs. Our summers in Germany are extremely humid and increasingly hot, which makes the air able to even store more humidity... Spanish plumes for 6+ months keep us nice and toasty. The landscape changes to a desert.
If you can get a motor without the flats, you should be able to grind flats on it fairly easily and repair it.
No doubt he just wanted an excuse to take the rest of it apart.
This is crazy. I was just now looking at buying one of these dehumidifiers for my basement. Like LITERALLY a minute ago 🤯
It is not crazy, it is Google...