Comment on Question: Humidity controlled cabinet
Blue_Morpho@lemmy.world 2 days ago
Are you sure it’s 35% ? I’ve found those cheap digital hygrometers to be off by 10-15%.
I bought a box and some say 10 and some say 20. I ended up buying several different brands and price ranges of hygrometers to try and figure out which ones were correct.
I use cereal boxes with desiccant and without any active dehumidifier they stay at ~25% despite being frequently opened and closed. So like others suggested, put a large flow-through bin of desiccant in and forget about it.
Fmstrat@lemmy.world 2 days ago
It’s a compressor, which is probably the problem. I’m using a DH11 on ESPHome, so am pretty confident of the accuracy. (I designed these nowsci.com/only-sensor)
AnyOldName3@lemmy.world 1 day ago
The DHT11 has been replaced twice with similarly-priced but more accurate models, first the DHT22 and then the AHT20. In my experience, the AHT20 is a lot better than the DHT22, mainly because its power consumption is far lower, so it doesn’t mess up its readings by getting hot.
Also, at that size, I’d be very surprised if the dehumidifier has a compressor. It’s much more likely that it’s got a Peltier plate, and they’re not very good. They use a lot of power to develop and maintain a fairly small temperature difference, so if they’re in a confined space, they heat up the air quite a bit, and then the water from their tank will more easily evaporate.
If you’re willing to spend some money, a solid state ion membrane dehumidifier might be better for a small cabinet than a compressor-based one, as it’ll be easy to ensure the water goes out of the cabinet instead of into a container that can’t be emptied without opening the cabinet and letting more humidity in. They’re definitely not cheap, though. I think they’re still under patent as there’s only one manufacturer that I can find, so maybe they’re the dehumidifier of the future even if they’re not suitable right now.
Fmstrat@lemmy.world 15 hours ago
While I’d rather have 2% accuracy than 5% on paper, it’s been fine, and checking with higher quality sensor has always put me within 1%.
Also, I mentioned in another comment it was a peltier, and I’d love to do SS but just soooo expensive. :(
Blue_Morpho@lemmy.world 2 days ago
Re: flow through
A mesh like container so all sides are exposed to air. Many 3d printed designs have channels so air can get into the middle of the desiccant container.
Fmstrat@lemmy.world 1 day ago
Ahh thanks. Also, as a correction, this thing may be a crappy peltier dehumidifier.