This may be the answer to getting the flower VPD higher

[flylowgethigh]

Humidity is my downfall. It is hard to keep a room under 40%. This technology may help.

The Silver Bear Cafe

www.silverbearcafe.com

 

[f-e]

That's very interesting. Though I wouldn't call a room at 40% a downfall, it's ability to still perform well at 30% is promising.

 

[flylowgethigh]

The room at 40% still has the tent at 47+%. I need the room down around 30% somehow. I pull a lot of water with the dehuey - enough to keep the reservoir of the big tent supplied.

 

[mojave green]

What’s your current VPD?

 

[crimsonecho]

so is this out yet?

 

[f-e]

The room at 40% still has the tent at 47+%. I need the room down around 30% somehow. I pull a lot of water with the dehuey - enough to keep the reservoir of the big tent supplied.

Oh yes, tent in a room.
Could you use a small split? Perhaps just your dehu reconfigured as such. I imagine the cool dry air straight off the evaparater might be of use.
Desiccant based is your next step. Like in the link. The problem is the continuous duty you require. It limits the choice. You kinda need two, for while one dries. They come as one box though. You would take that cold dry air from the evaporator of a compressor based system. Run it through the desiccant based unit. Then heat it. Perhaps through the condenser of the compressor based unit. Having had an airconditioning engineer split it for you.

Really a lot of work to get that RH figure down. Might be better to increase the airflow through the tent. Pots to buds, then out the building.

 

[flylowgethigh]

They said the stuff the U Tejas folks have come up with is scalable and cheap. If it doesn't outgas, and the water stays clean when it gets recovered, that is pretty cool tech for dope growers IMO. Patents to be had that's for sure. I'll give away the ideas here so us stoners can have the tech free. This is just a guy thinking out loud anyways.

With what I have and am doing now I can keep my tents 24-25*C and under 50% rh. That is night and daytime, but the transitions are a little warmer because of thermal mass. I can see making the inlet air filter box that houses the fan have replaceable panels of this stuff inside, maybe set-up like air-filters with standard dimensions - my house uses 20 x 25" - and I am making a box to use that size. Slide in a replacement panel as needed, and dry out the one you took out. The room draws the air down to 40-45%, and the panels are used to go lower when needed.

I would love to be capable of 25-30% rh in there with 68-70*F temps at night.

 

[f-e]

I did wonder about how long it might last. If it came to the public at $2 for 10L of desert water, you might be happy to pay that every day. Or at least pack one in your go bag. however, if you have to change it, or wash it, every day.. They probably won't make the floor standing appliance that we want.

19 pint, $250 desiccant dehu https://www.amazon.com/Ivation-Smal...=desiccant+dehumidifier&qid=1653455242&sr=8-8
If you used a typical dehu, like you have already, you could make a split. Physically, the dehu is a pair of radiators. Cold then hot. With a fan to pass the air through. You just need separate them. Perhaps move the hot out, and above. Once your dehu is cold and damp, you use the desiccant unit to full effect. What it produces, can go through that hot radiator, to lower the RH further.

A little reading gives the idea compressor based systems are used down to 30%. That's coming from the manufacturers of both types. While reading about desiccant based systems. So I tend to trust it. Though most compressor based units suck a it 40%. Not all work at low RH equally. While even fewer tell you. My 25L unit does 7L as 20c 50%, but don't tell you any lower. They rate their desiccant ones at 60% and 80%. They are not half as good as compressor one's of similar size and price.