so I just purchased a AC/Dehumidifier/Fan combo unit(https://www.amazon.com/DeLonghi-A120E-000-BTU-Portable-Conditioner/dp/B00168LKW2) I installed it inside my tent and vented it the unit outside a window. I read that it should dehumidify around 85pints a day which should be good enough for my 5x5 tent. Only problem is it's been running for a few hours and there is no difference in the RH I'm in week 5 of flower and it's still at 55%-60%. Why isn't my humidity going down? The lights are air cooled and the tent is exhausted through a carbon filter. There is no active intake. I have 2 fans moving air in the tent. What should I do to lower my RH? This was a really expensive unit I purchased and it should definitely do the job I don't know why it isn't?
Dehumidifier not working RH stays the same
- Thread starter Sam1510
- Start date
chemphlegm
Well-Known Member
adjusting the humidity setting to something other than the default setting of 55-60 will work.
some of these units will "run" all day and night, regardless of the current rh or unit settings.
during the running cycle if the room rh rises above the setting the unit then "runs" its compressor.(?)
Warmer air will be noticed coming out of the unit during this period, when rh meets setting the compressor(?) shuts down while the unit continues to circulate air.
also check google for dehuey recalls. I took pics of mine, followed directions and they sent me a brand new bigger one for free
some of these units will "run" all day and night, regardless of the current rh or unit settings.
during the running cycle if the room rh rises above the setting the unit then "runs" its compressor.(?)
Warmer air will be noticed coming out of the unit during this period, when rh meets setting the compressor(?) shuts down while the unit continues to circulate air.
also check google for dehuey recalls. I took pics of mine, followed directions and they sent me a brand new bigger one for free
The unit I have doesn't have an option to set the humidity it just has a dehumidify option and everything is automatic when I go to it 
natureboygrower
Well-Known Member
is the dehumidifier collecting water?
ok,I just looked at the unit on amazon.I'm a little suspicious about it not needing to be emptied.sounds like a great product,but I like the "old school" dehumidifier where I can actually see the water in the bucket.never used these newer style units.it would be interesting to see what would happen with just a dehumidifier in there
ok,I just looked at the unit on amazon.I'm a little suspicious about it not needing to be emptied.sounds like a great product,but I like the "old school" dehumidifier where I can actually see the water in the bucket.never used these newer style units.it would be interesting to see what would happen with just a dehumidifier in there
a senile fungus
Well-Known Member
Your blower might be pulling more humid air into the tent than the dehumidifier can handle.
No active intake my tent is in a basement only exhaust and fans moving air in tent
So it's weird I ran the ac/dehumidifier ducting back through the tent with the hot air blowing back in the tent and my RH was dropping I haven't checked if any water is coming but I ran a hose through a drain from the back of the unit. I haven't checked to see if there is a bucket inside the unit too.
I'm gonna take the duct off i had it running straight outside before when it wasn't working but now its routed back in the tent though another duct hole lol. I'll take off the duct and let the hot air blow straight from the back of the unit I think it will dehumidify more better. I think I messed up by letting the hot dehumidified air blow outside before
a senile fungus
Well-Known Member
If your exhaust is removing air from the tent, then air from outside the tent will attempt to fill the void. Are you exhausting to the outdoors? Exhaust is going where?
Do you know the humidity of the room that the tent is in? You may be better off trying to control that environment vs attacking it inside the tent.
Not 100% sure (someone feel free to correct me lol) but I believe that air that is a higher temperature is able to hold more humidity, up to a certain point. So, relative humidity is more a measure of the percentage of potential saturation, vs an actual humidity value, all relative to temperature and pressure. Therefore, the same humidity value might have a lower or higher RH value depending on temperature. And pressure.
So, I dunno if that has anything to do with anything.
Also, can you post a pic of the unit? Is it a portable a.c. with one single hose coming from it or? ... I jerryrigged a wall unit to be a stand alone, worked like a charm.
And you should probably do a visual on the drainage situation. If it's working it'll be draining water, so that's something to confirm.
I've read that some of these unit actually use the condensate to cool the unit itself, so I wonder if the exhaust air is laden with water vapor.
Which leads me to another question. How are you measuring? Via the unit? Handheld hygrometer?
One last thing, are you using the a.c. setting on the unit, or is it set to dehu?
Sorry for so many questions LOL, just realized how high I was and how long this post is. But you know how trouble shooting goes...
too many bong hits of gg4 and blueberry this am 
I'm using the dehumidify option and it just has one setting that starts dehuimifying.
its all good I do the same shit haha, but I'm using a hygrometer and I have it set on the dehu setting. I took off the ducting behind the unit and it's working now, the RH went from 55% to 40% it just raises my temps by 10 degrees f but that's okay it just means I could take out my space heater now since my tent was at 60f Without any heater/dehu and now 70-75f with the dehu only running I looked at the hose connected to the back and so far no water a little condensation tho but it is dehumidifying for sure I'll post pics when I get back to my gardenIf your exhaust is removing air from the tent, then air from outside the tent will attempt to fill the void. Are you exhausting to the outdoors? Exhaust is going where?
Do you know the humidity of the room that the tent is in? You may be better off trying to control that environment vs attacking it inside the tent.
Not 100% sure (someone feel free to correct me lol) but I believe that air that is a higher temperature is able to hold more humidity, up to a certain point. So, relative humidity is more a measure of the percentage of potential saturation, vs an actual humidity value, all relative to temperature and pressure. Therefore, the same humidity value might have a lower or higher RH value depending on temperature. And pressure.
So, I dunno if that has anything to do with anything.
Also, can you post a pic of the unit? Is it a portable a.c. with one single hose coming from it or? ... I jerryrigged a wall unit to be a stand alone, worked like a charm.
And you should probably do a visual on the drainage situation. If it's working it'll be draining water, so that's something to confirm.
I've read that some of these unit actually use the condensate to cool the unit itself, so I wonder if the exhaust air is laden with water vapor.
Which leads me to another question. How are you measuring? Via the unit? Handheld hygrometer?
One last thing, are you using the a.c. setting on the unit, or is it set to dehu?
Sorry for so many questions LOL, just realized how high I was and how long this post is. But you know how trouble shooting goes...
GNOME GROWN
Well-Known Member
while running a portable ac in dehu mode you need to remove the exhaust hose from the unit and let that warm air dump into ur tent! im running a portable ac on dehu mode right now cause my dehu shit the bed.
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a senile fungus
Well-Known Member
Where does the water go? ???
GNOME GROWN
Well-Known Member
Theres a drain plug on the bottom of the unit. You need to drain the water to a resi or drain it outside if you can. I have my portable ac on a small 2 foot tall table and its draining into a small rubbermaid bin. dump it everyday when the lights come on
It's weird cuz mine ac/dehu was advertised as "dripless technology never empty a bucket again" I've been running it for almost 24 hours and still no sign or water anywhere it's a mystery lol maybe there's a bucket somewhere behind one of the panels
How do you control all the heat it gives out if you can only use 1 option at a time?
a senile fungus
Well-Known Member
Some of these units use the water the cool themselves.
The AC setting should still dehumidify, while cooling as well. But I don't have a portable, so I presume these things.
GNOME GROWN
Well-Known Member
I'm only using it as a dehu right now. It's winter here so I don't need ac in my grow. I have my exhaust fan hooked up to a temp controller set to 73 degrees for day and night temps so any time my rooms hits 75ish degrees the fan turns on for a few minutes and exhausts the hot air out, turns off when the room gets down to 70. If you're running a portable ac in dehu mode and exhausting it out a window its not going to do much or anything at all to the humidity in the room.