homemade greenhouse dehumidifier; ideas?

[Ganico]

I was thinking of something like this


A big rubbermaid bin or a trashcan with a drain (just plastic tubing running from hole in bottom) that contains a coil of 1/2" copper tubing, with a fan drawing air from one side, and over the coils, then out the fan.

Above the bin/can with the coils, would be a bucket filled with ice and then filled with water, and with a lid on top. Or maybe even a "water chiller" in a bucket of cold water.

So one end of copper tubing starts at the bottom of the bucket, then it goes down to the box where it coils, and then comes back up to the bucket.

Maybe even add a fishtank pump to keep it circulating




My idea is that the temp difference will make condensation from the air that passes over the coil, removing moisture.


Sound feasible?

Any ideas, input, critiques,etc are welcome.

 

[AriesXX]

You down in the hot and humid South huh? That sounds like a great way to use condensation to remove the moisture from the air. I have no idea how efficient your system would be, but the key would probably to seal your greenhouse from the outside air, but then you might run into CO2 problems. Would it work for you to just rig up fans at either end of your greenhouse and keep the air moving? I bet if you look, there are tropical strains that would thrive in your area. I know Thailand is VERY humid and hot, so maybe you could grow a Thai hybrid? Hope that helps

 

[Ganico]

Yeah, in the deep south. I don't even have a greenhouse, but I'm looking for a new place and was thinking about building a small one whenever I move.

But yeah, a dehumidifier might not even be necessary anyway, it's just that it gets really humid here and I was thinking that it'd be too high in a small greenhouse. I tend to over-analyze things though

And I only fool with sativas and sativa doms really. So I'm gonna do some Thai hybrids regardless of the greenhouse though, but thanks for the suggestion, haha.

 

[Guest]

Any other ideas on doing this? I dont want to vent my GH if I dont have to.

 

[river rat01]

from what ive been reading about greenhouses, venting is nessasary because the humidity will get too high leading to mold growth.

also without fresh air, co2 would be depleted by the plants in no
time.

but, you could just add an air conditioner and co2.
i dont see why it wouldnt work.

 

[globel]

I use a dehumidifier in my sealed room. I don't know exactly how it works but i know the air coming out is warm almost hot. I dont think it just flows air over cold coils. I think it heats it up after going oferthe coils. What you maid ssounds more like a SWAMP coolor or a water coil air conditioner.

instead of water pump freon through the coper and on the end put a restricter so it causes the freon to freez when you condense it. that would be super cold fyi

 

[Me2]

How about this?

Run a curtain of cool/cold water down the inside of a length of clear layflat poly tube (3ft wide stuff). Use a spraybar type arrangement to spread out the flow.

Hang the layflat tube(s) up in the gh supported by the spraybar, seal the top and put the open bottom end in a res to prevent the humidity inside the layflat from escaping into the gh.

The warm humid air in the gh hits the cool surfaces of the layflat (due to the water curtain inside) and drops it to dewpoint, the water condenses on the outside of the poly and runs down into the res.
If the layflat is 6ft long x 3ft wide you`ll have 32sqft of cool surface to work with (18sqft each side). It won`t block light if you hang it on the north wall side.

The downside is the phase change will transfer a fair amount of heat to the water in the process so you`ll need a sizeable res.. or use the free heat for an outdoor swimming pool maybe?

 

[BonsaiBud]

This should do it for ya:
http://cgi.ebay.com/DUCTLESS-MINI-S...ryZ20711QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
mini split air conditioner.
You could get a little 9,000 BTU one for $500, but best to play it safe.
As for a sealed room: ok, so you add CO2, but won't the oxygen build up to toxic levels? You should draw air from your house. It will be climate controlled and fortified with the CO2 produced by you and your mates. Keep the greenhouse under negative pressure and exhaust with a carbon filter or ozone.