Mini review of the rechargeable dehumidifiers I’ve tried.
Gurin* or Gero* or Ivation*
These dehumidifiers use a short cord (ungrounded figure 8 style) and hold more silica gel than the others listed here. They are thicker, take longer to recharge than the Eva-Dry (about 12 hours), but also last longer. I mostly buy these now as I find using the standard power cord more convenient than the built in plug kind. Be careful to keep them apart when they’re plugged in, the plastic case can melt if you put them too close to one another while recharging. I’m not sure if there’s any difference between the Gurin and Ivation models, I’ve only bought the Gurin versions as they’re usually cheaper.
Eva-Dry E-333*
These are convenient, they plug directly into a wall with a folding plug, and recharge fairly quickly. Build quality is better than the Gurin dehumidifiers. If you only need a couple dehumidifiers, these are a good option, but it’s inconvenient if you need to recharge a bunch at the same time (though a powersquid* can help with that issue). They recharge fairly quickly, usually in a few hours.
LaGute*
This is my least favorite of the plug-in dehumidifiers I’ve tried. It looks nice, has a LED light, and like the Eva-Dry, it plugs directly into the wall with a folding plug. The problem is the indicator, it uses orange-green indicators (which should be less toxic than the blue-pink ones), but I don’t see it change color during normal use. The blue-pink indicators gradually change color, but I’ve left this one out for days without seeing any color change. The only time I’ve seen it change color is when it’s recharging and the moisture leaving the silica fills the indicator capsule. It’s also significantly smaller than the Gurin or Eva-Dry models listed above. Makes a big mess if you take it apart.
I did some more testing, and the change from orange to green happened a couple of days after the other dehumidifiers had changed completely from blue to pink when they were left out at the same time. By that time its effectiveness was pretty much non-existent.
Small metal dehumidifier*
Requires recharging in the oven, which is too far away.
Assorted bags of silica gel
Requires recharging in the microwave or oven, which I’m too lazy to do, I have no idea how long they last, and you’d need some other indicator of when they’re saturated. I also don’t running microwave ovens to dry these as I’ve been told it’s not good for the microwave.
Humidity Meters (round* or rectangular*)
Not the most accurate, as you can see in the picture, but good enough to let me know when it’s time to recharge the desiccant. I tape these to the inside of my filament storage containers, it’s easier than pulling out the dehumidifiers to check the color of the indicator.