Anyone tried a peltier dehumidifier in a grow tent?

[roperman]

I'm 4 weeks into flower and my grow tent humidity is between 60 and 70 percent humidity, which sucks. I ordered a $50 smallish dehumidifier that will take out some of the water from the air inside the tent.

Anyone had any luck with these? They run on the Peltier technology where one side gets hot and one side gets cold, and they use the cold side to condense the water out of the air. It doesn't use a big compressor like most dehumidifiers. It also doesn't take a lot of water out of the air either, but I'm thinking that it's a small enough space where it might make a difference.

The one I ordered: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[Locrian99]

I was curious how well these would work as well

[abadtrip]

I use 1 in my drying closet in the summer to bring the humidity down to s manageable range it works well in that small space

[UrbZ]

What size tent? If anything smaller than like 8x8 or 10x10 tent you will run into major heat issues guaranteed. A unit that big will create heat, my dehumidifier brings an entire room up 5-8 degrees i couldnt imagine what it would do inside of a small tent. prolly cook my plants like an oven.

All electronics create heat to do their process no matter what.

You shouldnt try to drop the RH in the tent. RH outside the tent needs to be brought down then circulated inside. IMO

If you ask anyone whos ever tried to run a dehumidifier in a tent, it doesnt work out well.

[PRIMO]

I believe these are powered by 9.5 volts I wouldn't think they could generate much heat.

[UrbZ]

It doesnt really matter what voltage electronics dont work that way. Heat is created by the process of what the electronics do. Not necessarily how powerful they are.

I have a 12v volt radio that creates no heat when running.

I also have a 12 v battery charger that gets to hot too touch when running.

The differences is what the 12 volts are used for.

Say you have something 12 volts at 2 amps this will create barely any heat. But say you have 12 volts pushed by 20 amps. This will be scalding hot..

This is a basic principal for all electronics. What I went to school for.

Not only that this unit specifically talks about using heat sinks and using hot and cold air itself to dehumidify the air.

Here is a link on how these systems work.

http://www.dehumidifierbuyersguide.com/thermo-electric-dehumidifier-reviews/

[UrbZ]

This unit is smaller than I first thought. So I figure in an 8x8 with good ventilation it would work fine but in a small 4x4, light heat (even with leds) plus this unit will give heat issues I am almost 100% positive.

[oldjarhead100]

I run a 70 pint a day dehumidifier in my bloom room heat is not an issue the DH heats up when it has to do alot but once the humidity is down it doesn't put out alot of heat , I will say that I'm planning on shutting down inside June 15th until Aug to avoid the humidity in the cellar

[DoctorJohnson]

Just FYI, the Peltier effect, while very interesting, is extremely inefficient (and thus expensive).

[Paracelsus]

Have you thought about desiccant or rice?
don’t laugh it works. I use wet towels to humidify.

https://en.m.wikipedia.org/wiki/Desiccant

[Gurnsy]

Anyone ever tried using damp rid? They are white crystals in a container that attract moisture/humidity. People usually use them in their closet/wardrobe.

[UrbZ]

I have. They dont work for much. I put 2 buckets in 1 tent dropped 2% RH in 26 hours then it plateud.

[Paracelsus]

Anyone ever tried using damp rid? They are white crystals in a container that attract moisture/humidity. People usually use them in their closet/wardrobe.

See My post above yours concerning desiccant

[GreenhouseEffect]

Hey Roperman,
It looks like you grow in soil too, have you tried staggering your watering schedule?
I started watering everyday, but only one or two plants each day, so with 5 plants in a tent, I'll water one plant one day, then it's neighbor the next day, and so on, so that I don't add too much moisture at once. I do grow in a raised bed, which maybe makes it work better, but it has been helping since I started doing it that way.

[roperman]

The thing came tonight. It draws 60 watts so I doubt if it will put out more heat than the tent can handle. It's a 4 x 4 tent. I'll report how it works. I have 30 days to return it, so at least I can move on to plan B if it doesn't do anything.

Keeping the humidity down outside the tent is a good goal and it would probably fix my problem. But the only place we could put this tent was my office and I can't have a noisy dehumidifier in there. I have a spare one in the basement and it's really loud.

I'm doing my first coco grow so I've been watering frequently, every day or every other day, which does put a ton of moisture into the room. From what I've heard, plants grown in coco do well with daily watering. I can try going every three days and see if it helps.

Thanks for all the suggestions.

[Locrian99]

Please post your results. I’m curious

[oldjarhead100]

if you water coco every 3 days it works well but you have to keep an eye for lockout problems , the nutes build up salts after a couple of weeks , when I did it that way I watered with nutes then after a couple of weeks I would water with plane water just use twice as much water to wash out the build up

[roperman]

Complete bust. After 24 hours, the "dehumidifier" collected a whopping 5 ounces of water. I did hook it up to my kilowatt meter and it was drawing 60 watts or so, but the thing just doesn't pull out enough moisture from the air. I think if you had three or four of these going at once, it might do something. It would certainly add some heat to the tent if you had a few of them running.

For a test, when the lights went out, I turned off my exhaust fan so there was no air moving in or out of the tent. I watched the humidity level start at 61% and remain unchanged for the next six hours. So the thing is not effective at lowering humidity, AT ALL. Back it goes.

I have a 4 x 4 tent with two plants, in 5 gallon cloth pots, in coco. When I water, if I wait three days, with 1.5 gallons going in, about a quart comes out from each plant. So after watering I have roughly two gallons of water that will evaporate over time and really pushes up the humidity in the tent. Luckily the humidity in my office has gone down to about 40% so at least the air being sucked into the tent it drier than what's inside. This morning the humidity in the tent was around 50% which was a relief. I don't want powdery mildew or any sort of rot going on in there.

I thought about staggering the watering schedule so only one plant would be watered at a time (thanks GreenhouseEffect), but I decided in the end that it may not make much difference. I'd just have water going into the tent nearly every day instead of every three days. I'm hoping the second and third day after watering will be drier inside the tent.

[Locrian99]

Are you not removing the run off? Could help a little to do so. I use a shop vac and suck the run off out, 18” saucer with a 14” riser.

[roperman]

Yes, run-off is removed after it all drains out. I have the pots up on a wire mesh shelf, about six inches high, and there's a plastic storage bin that collects the water below. I dump the bins after the plants stop dripping. I've only got the two plants in the 4 x 4 so I have room for that.

[Locrian99]

Ah nice

[PRIMO]

I'd have to put the dehumidifier in my office/growroom then, turn it on when I leave said room. And when I come back in... Turn the annoying bastard off & turn on the tunes.

[ajax]

I have tried about a dozen different humidifiers.
My preference is top fill, ultrasonic.
These put out dense, low-velocity fog that needs to be blown around the tent by a fan placed below or behind the fog.
I have two of these in a 3 x 3 x 8 tent sitting on speaker stands a few feet above the floor, along with one heater.
I leave mine on 24/7, but the humidity will go up a lot if the temp drops during lights out.

Bottom fill humidifiers are a pain, and I won't use one.
Forced air, non-ultrasonic humidifiers might work in your space, but they put out far less humidity than ultrasonics.
It's important to use only distilled or RO water in the ultrasonic types. Otherwise, your plants will be snowed on by potentially harmful "white dust."
The same argument might apply to forced air types to save on replacement filter/wick costs.
Here's my most recent purchase: