Eva-Dry E-333 Review

The E-333 is one of two different rechargeable moisture absorbers manufactured by Eva-Dry – the other being the slightly heavier duty E-500. Both units remove moisture from the ambient air by adsorption (adsorption, not absorption, is the technical term for this process). Inside the E-333 and E-500′s outer plastic shell is a silica gel which facilitates this adsorption. Once the silica gel reaches capacity (the point at which its saturated and can no longer remove any more moisture) it changes color from blue to pink. On the outside of the E-333 and E-500 is a small indicator window that shows the color of the silica gel so you’ll know when this happens (when it reaches capacity). When the desiccant (silica gel) reaches capacity you’ll need to recharge the device. This involves plugging it into a wall outlet. The electricity from the wall outlet will heat up the desiccant and liberate moisture from it. This acts to “recharge” the device. The recharge process takes about 8 to 10 hours for the E-333 and 10 to 12 hours for the E-500. Note that since the recharge process involves the liberation of moisture you’ll want to recharge the device outside or in a well ventilated indoor space such as a garage or utility room, not the room or space that you’re trying to dehumidify.


Moisture Removal Rate

The E-333 has a moisture removal capacity of 4 to 6 ounces. Eva-Dry states that the E-333 will reach this capacity after 2 to 4 weeks of use, depending on the conditions of the space that the unit is dehumidifying. In more humid and warmer conditions you can expect the E-333 to reach capacity more frequently (once every 2 weeks or so) while in less humid colder conditions you can expect it to reach capacity less frequently (once every 4 weeks). Note that even in the most humid, warmest conditions this unit will not reach capacity until a few weeks have passed.

Compare the E-333′s moisture removal rate of 4 to 6 ounces per 2 to 4 weeks to that of its primary competitor, the Eva-Dry E-500, which removes 6 to 8 ounces of moisture per 4 to 8 weeks. Thus, the E-500 removes about 50% more moisture than the E-333 but takes 100% as long to do so. So, the E-333 removes less moisture per recharge but removes moisture faster than the E-500. Note that despite the fact that the E-333 removes moisture faster than the E-500, it remove moisture slower than almost every other type of dehumidifier we’ve tested and reviewed.

The average compressor based dehumidifier removes 30 to 70 pints (approximately 500 to 1000+ ounces) of moisture per day. The average thermo-electric dehumidifier removes about 10 ounces of moisture per day. Full size desiccant dehumidifiers remove about 20 pints (approximately 300 ounces) of moisture per day. The E-333 and similar devices should therefore only be used for extremely mild humidity problems in extremely small spaces.

Outside of specifying this device’s area of coverage (a topic which we’ll discuss in detail next), Eva-Dry does a good job of pointing consumers in the right direction as far as what the E-333 is capable of. The manufacturer recommends this device for small spaces such as closets, pantries, kitchen cabinets, and small bathrooms – all spaces in which the E-333 can certainly work well to reduce dampness. Eva-Dry also recommends the E-333 for small spaces in which dampness can cause odor problems. Examples include washing machines and gym bags.

Area of Coverage

Update: Contrary to the statements we make below, the manufacturer does not give the “area of coverage” for either the E-333 or the E-500 in terms of square footage. Instead, it is given in terms of cubic feet – a volume. Thus, much of the discussion below in which we incorrectly refer to the E-333′s area of coverage as 333 square feet and the E-500′s area of coverage as 500 square feet does not apply. The E-333′s actual area of coverage is 333 cubic feet and the E-500′s actual area of coverage is 500 cubic feet.

Eva-Dry specifies that this device can work in areas up to 333 square feet, hence the model name for the device which is the subject of this review, the Eva-Dry E-333. The E-333′s manufacturer specified area of coverage is approximately 150 square feet less than the E-500′s manufacturer specified 500 square feet. We disagree with both of these “manufacturer specifications”. 500, even 333 square feet is a sizable area – an area larger than what we believe these devices are capable of dehumidifying.

To put this type of square footage in perspective imagine two different rooms, one that’s 333 square feet and another that’s 500 square feet. Our example 333 square foot space is 33 feet long and 11 feet wide. Our example 500 square foot space is 25 feet long and 20 feet wide. These are sizable spaces. As we discussed above, Eva-Dry recommends the E-333 and E-500 for small spaces such as closets, pantries, small bathrooms, etc. Do any of these spaces have anywhere close to the dimensions of 33 by 11 ft or 25 by 20 ft? The answer is no. Thus even Eva-Dry themselves don’t recommend these products for any type of space with the same dimensions as their specified area of coverage of 333 or 500 square feet. Why then does the manufacturer attach these large overblown square footage numbers to what they themselves call mini dehumidifiers?

We believe that manufacturers of low capacity light duty dehumidifiers give such high area of coverage specifications so that consumers look toward these numbers, instead of moisture removal rate, when comparing inexpensive mini dehumidifiers to more expensive large full size compressor based dehumidifiers. The top rated Frigidaire FFAD7033R1, an approximately $250 compressor based dehumidifier, is specified by its manufacturer to be capable of dehumidifying spaces up to 2500 square feet. The E-500 with a manufacturer specified area of coverage of 500 square feet is thus inferred to be capable of dehumidifying spaces only 1/5 as large as those spaces that the FFAD7033R1 can dehumidify. Thus the consumer is inclined to think that the E-500 is 1/5 the dehumidifier that the FFAD7033R1 is. The E-500 at approximately $30 is almost 1/10 as expensive as the FFAD70333R1 and so the consumer is also inclined to think that the E-500 is the better value. Keep in mind that the device’s area of coverage is in its model number – E500 = 500 square feet of coverage – easy to see and immediately makes the consumer aware that this is the size space that this mini dehumidifier should be capable of dehumidifying.

Note: Our comments regarding the unit’s moisture removal rate, its value, and situations in which we recommend its use still apply.

Buried within the product description for the E-500 is the fact that it only removes 6 to 8 ounces of moisture and that it takes 4 to 8 weeks to do so. Thus the E-500 removes less than 1 ounce of moisture per day. For the sake of this discussion let’s say that it removes 8 ounces of moisture in 4 weeks. 4 weeks = 28 days. 8 ounces divided by 28 days = approx. 0.3 ounces of moisture removal per day. Compare this number to the 70 pints = 1120 ounces of moisture that the FFAD7033R1 removes. 1120/0.3 = 3733.33. In other words, the FFAD7033R1 removes almost four thousand times as much moisture per day as the E-500 at less than 10 times the cost. When comparing moisture removal rate, the larger compressor based dehumidifier is clearly the much better value.

That being said, such a large dehumidifier would be overkill for a small only mildly humid space. The E-333 and E-500 certainly have their uses and we recommend them for the same spaces that Eva-Dry recommends them for – damp closets, cabinets, etc. We strongly disagree with Eva-Dry, however, on the size of the spaces that these devices should be used for. We would not recommend either the E-333 or the E-500 for any space larger than about 50 square feet. Either device, in our opinion, is simply not powerful enough to dehumidify any space larger than approximately 50 square feet.

Final Thoughts

At approximately $20, the E-333 is a very inexpensive solution to mild humidity problems (and by mild we mean very mild). The E-500 is about $10 more expensive and it does have a slightly greater capacity than the E-333, but it also takes much longer to reach that capacity. Thus, the E-500 has a lower moisture removal rate than the E-333, at a greater price. Between these two devices, our recommendation is the E-333 for two reasons – for one, it’s cheaper and two, it removes moisture faster. Only buy the E-500 if you value its greater capacity and thus also value the fact that you’ll need to recharge it less frequently.

At approximately $20, we’re also inclined to compare the E-333 to the two DampRid products we’ve tested and reviewed. The FG50T and the FG83LV remove moisture in much the same way as the E-333 does – a chemical desiccant removes moisture from the air by adsorption. The major difference between both DampRid products and the E-333 (and similar products) is the fact that the former cannot be recharged (they’re disposable) while the latter can be recharged and reused for up to 10 years. Thus, by purchasing either the FG50T or FG83LV you are saving about $10 in initial cost (both products retail for about $10) BUT they can only be used one time. Thereafter you’ll need to throw them away and possibly will need to replace them (costing another $10 (approx.) and already putting you at about the same price as the E-333). Thus, our recommendation is that you buy those DampRid products only if your humidity problem will be taken care of by buying one tub of the FG50T or one pack of the FG83LV. If you have any reason to believe that you’ll need to buy another tub or another pack in the future our recommendation would be that you buy the E-333 or the E-500 instead. Both Eva-Dry products are also “wireless” (thus they can be used in places such as a car) like both DampRid products and both remove about the same amount of moisture per unit time as both DampRid products. The difference again is that the Eva-Dry products are rechargeable while the DampRid products are not.

Finally, we want to warn again (as we did above) that the E-333 does not serve as a replacement for large compressor based dehumidifiers. It will not be able to dehumidify a severely and/or perpetually humid space, no matter what size it is. Again, the E-333 removes less than 10 ounces of moisture over the course of several weeks of dehumidification. If your humidity problem is severe and/or the space you need dehumidified is large our recommendation is that you read our general dehumidifier buyer’s guide and purchase a full size compressor based dehumidifier.



  1. kenny ramirez says

    I got my eva dry today and I was just wondering how to turn it on, my crystals are orange which is dry and I put it in my reptile tank and the hygrometer doesn’t seem to have gone down with the humidity. I was just wondering if there is a turn on button that I don’t know about.

    • Admin says

      You are using it correctly. The E-333 may simply not be removing moisture fast enough to make a tangible difference in the space where you are using it.

  2. shutterbug says

    Would the 333 do a good job of removing moisture from camera and lens stored inside a zipped up closed 36″ x 20″ x10″ camera backback?

    • M. Henderson says

      We purchased the E-333 several years ago solely for use in our home safe. It works VERY well! Recharge on the first of every month and it has never failed. Great product!

  3. Scott Barrett says

    Would two E-333′s be suitable to dry a boat cuddy cabin that is tightly shrink wrapped and put in storage over the winter (Oct – May) in Vermont? The cabin is about 13x 7x 6.

    I typically use 2 Damp Rids and that does the trick. Wondering if the E-333′s would work as well.


  4. Jesse says

    The wire hanger doesn’t hold tight enough to be hung while going down the road. Ours fell off, the hook was still in place where it had been hung. The “Fill Door” on the E-333 popped open and all of the various sized beads went everywhere. Two trips out and we’re still finding beads rolling out from under stuff and we cleaned all we could see every morning for two weeks. The fill door should have been sealed permanently but isn’t.
    How well does it work? We really didn’t get a chance to find out. Would I buy another one? Probably not, to PO’ed to give it another chance. Also don’t buy at Camping World the price is way more than most anywhere online.

  5. Matthew says

    I believe I asked this for another item as well, though I can’t see the comment now. Would this be suitable for a refrigerator? I am getting a lot of condensation which is forming ice beneath (and in) my crispers.

  6. Steve Most says

    I have a problem when leaving my 2 door car in a humid environment that when I leave for a few months, mold starts to grow. Will 2 of the Eva-dry 333 or 500 units perhaps be better than the Damp rid I have used that although it pulled out a full batch of water, there was a bit of mold I had to deal with when I returned. I have a friend that can monitor and recharge if necessary.

  7. john paul says

    is there any Desiccant Dehumidifier have a capacity of >10.2 pints.
    by means of increasing of number of unit to be used, will the rate of removing RH increase?

  8. Jan says

    Do you think the E-333 will be sufficient or at least be helpful in removing moisture created by the washer/dryer combo in our camper? It’s in a closet with louvered doors. What if there were 2 of them since the combined price of two is about the same as the E-500. I read the review saying the E-333 removes moisture faster. I also thought about using one at a time so one could be charging while the other is in use. Your comments and recommendations, please.

  9. nope says

    it says cubic not square feet. i stopped reading your review when you said that they claimed the e-333 could dehumidify a 33 x 11 foot room. this would be true if the room was one foot tall. As the company is probably assuming most people aren’t house elves i think they mean more like a 4 x 10 x 8 room like a small bathroom, closet, or what else they put.

    • Admin says

      Thank you for the correction. We’ve placed a disclaimer over the relevant part of the review to note this mistake.

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