Since I started flowering and I need rh% lower it’s becoming a problem to keep it stable especially at night. I’m thinking the dehumidifier being inside the tent can be a big problem so I put this together on my dehumidifier. Lol I’m hoping it helps some. I just need opinions on if i should have it high in the tent like it is now or if it will work better being placed towards the bottom ? Also with humidity outside being high should I keep my exhaust on a lower speed setting ? or a higher setting wouldn’t matter much with maybe pulling in to much humidity and the lower setting possibly helping keep humidity inside tent low ? Hope it makes sense lol appreciate any advice
It will imo definitely help lower the RH, but by how much is gonna depend on your tent exhaust capacity and make up air. Most (yours may be different) dehumidifiers work something like this A fan collects air from the surrounding area and pulls it into the dehumidifier. (so its pulling air in from outside your tent where the unit is sitting) As the air passes through, it comes into contact with the dehumidifier's cooled coils. These coils use condensation to pull moisture from the air. The collected moisture remains on the coils and drips into the dehumidifier's reservoir or out a tube to a floor drain (remember this is still the air the dehu is sucking in from outside your tent, not the much wetter tent air inside). The dehumidifier reheats the more arid air and exhausts it back into the room. (or in your case the tent). So like lets say the RH in the tent is too high (75% in this example) and you want to lower it. If you put the dehu in the tent, its sucking in the super moist air and pulling the moisture out, then spitting out drier air right into the tent (the water from the air going to the drip pain or drain line) With the main dehu unit outside the tent, you are removing moisture from the ambient air, then pumping that dry air into the tent (which is already like 75% RH). This will work, as eventually the drier air will either displace the wetter air out of your tent or if you have an exhaust system it will eventually suck a good bit of the wetter air out as you pump in dry air, but its not super efficient, as instead of removing the water directly from the problem area (tent) you are pushing drier air into the tent, which will eventually be displaced (and thus the tent will get drier) out of the tent either via exhaust or simple positive pressure as more air comes into the tent. The flip side of that equation is depending on the size of your grow area, you might have not have the physical space to put a dehu in the tent, or even if you could, the compressor and re-heater are going to raise the tent temps more than most folks like. The other problem is tiny dehu units that can be easily inside like a 4x4 usually are too small that they don't have drain lines, only a tank that needs to be emptied daily or more often depending on how hard the unit is working. What I have had to do in the past is take like a 1/2 inch drill bit, put my own hole in the tiny tank, superglue a hose barb fitting onto the hole I drilled, then run some like 1/2 or 1/4 inch plastic tubing from the hose barb down to wherever the drain needs to happen. Alternatively, if the "make up" air (the air in the room your tent sits in) has a decent RH like below 50%, you can just crank up the exhaust fans, they will pull more wet air out of the tent, and to equalize pressure new air comes in your tent flaps if you open them (or the tent walls start sucking in from the negative air pressure), if that new "make up" air in the room where the grow is located is decently dry enough, you may not need a dehu at all, just increase the number of air changes per hour through your tent, might take some doing and trial and error (up fan speed, see what it does to RH after 1-2 hours and it needed crank the fan up higher till you get where you want to be. Either way mate, what you are doing will work, I'm not trying to disparage you setup, as there may be more I'm not seeing to the grow, but whenever I'm in a situation where my tent RH is getting too high, everything above is typically how I go about fixing it, so hopefully this helps, apologies if it didn't.
What humidity numbers have you been fighting before trying this set up? How far along are your plants?
Thanks for the reply and yeah I should’ve went more into detail on my setup. I have an exhaust fan with carbon filter going to a window exhausting outside and another duct at the bottom coming from a window with a an intake fan only pulling in air from negative pressure. So the dehu I set up is pulling humidity out and not just venting out into the tent no more. And yes it helped a lot I appreciate it.
So before I set this up I had dropped my rh% to 40% when I switched to flowering. It would constantly drop and rise between 40 and 60 and sometimes even reach 70. I then set it at 50% so it wouldn’t be working that hard. On my controller I have the AH set at 60 and would hear the alarm quite often especially when lights were off and at those times I couldn’t do nothing just wait til lights came on and try to figure it out it’s was a headache. Since setting it up last night I heard the alarm once. Thinking about setting it up at the bottom opening on the tent. They are on day 16 of flower.
You’re running the dehumidifier through a controller? For the unit to operate effectively be sure the dehumidifier is set to maximum, lowest humidity. The humidistat in your controller will better operate the unit. But, this is how I would set it up: If your room where your tent is located isn’t too large I would set the dehumidifier in the room without connecting a duct to the tent. Also, with it outside the tent it should not be connected to your controller if the sensor is in the tent. Better to let your controller run your exhaust alone. Run the tent exhaust to draw the dried air into the tent’s intake. This should work because it sounds like you are in the tolerance range of 40-60% RH, which is ok.