Exausting outside of grow room

medidedicated

medidedicated

Well-Known Member
I know it will help a lot for humidity but never done it before. Wouldn’t the 100 square foot bedroom have negative air pressure, sucking in untreated air? Would the tent suck out the room air faster than a dehuey can treat it?

Considering upsizing to have two big plants in a 2.5x5 that is 6’ tall. I wonder what yall would do. Just vent into the same room or outside? Considering how high CFM fans are and could quickly vent out a space.

It would take some construction to do and would rather ask people who made many runs and tried both, maybe it is not needed or I can keep blue printing that.
 
medidedicated

medidedicated

Well-Known Member
Also considering getting two mars ts1000’s in there. Like the only light I can find that fits 2.5x2.5 on a budget.
 
RuggedWombat

RuggedWombat

Well-Known Member
Do a lot of research. I'm also working on cooling my home office which has my tent and it's 82 degrees currently. Maybe start by trying to cool the room itself? Air movement gets technical fast as air doesn't always circulate the way we imagine it does. Start by cooling the room and maybe some of the air can flow under the door for starters? Does the room have a fresh air vent connected to your HVAC? I'll be building a homemade AC unit at some point in another thread but it's basically a fan blowing over something cold which one of the oldest cool hacks in the book.
 
RuggedWombat

RuggedWombat

Well-Known Member
Even a container with some frozen 2 liter bottles in it near the intake will help cool it. If you have a booster fan even more so. Try not to overthink it as often there are very simple solutions that we just can't visualize yet. Also there are always people more creative than you so someone here already made a solution for $20 from Lowes or some shit I'm sure. I'm always impressed by the ingenuity here. I just bungee corded my fan and carbon filter and can't believe my dumbass used those nylon straps with the plastic buckles for 2 years...
 
medidedicated

medidedicated

Well-Known Member
RuggedWombat said:
Do a lot of research. I'm also working on cooling my home office which has my tent and it's 82 degrees currently. Maybe start by trying to cool the room itself? Air movement gets technical fast as air doesn't always circulate the way we imagine it does. Start by cooling the room and maybe some of the air can flow under the door for starters? Does the room have a fresh air vent connected to your HVAC? I'll be building a homemade AC unit at some point in another thread but it's basically a fan blowing over something cold which one of the oldest cool hacks in the book.
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It is about 120 square feet, has intake vent and one vent blowing in ac or hot air in winter. My last run in a 2x2 had exausted into same room and when dehuey shut off, the room rh reached 75% and 85% in the tent so that is why I figured it would help to exaust outside of it.

But exausting outside of room into outside the home I wonder if it would exaust the whole room faster (negative air pressure) Idk what would happen, I see people do this with bigger rooms, mines tiny.

I last applied the classic setup of dehuey outside tent and treating the grow room as lung room and it worked ok and perhaps might be enough if the tent was bigger and not over crowded, full of air circulation.

It wouldn’t go below 45% but it was a over crowded 2x2.
 
medidedicated

medidedicated

Well-Known Member
I was blocking the ac vent or opening it as the dehuey would heat up the space since it is a industrial like dehuey. I forgot to consider the intake vent was sucking out my treated air, whoops.

My mind goes blank wondering what will happen but if it is worth it and gives the extra control I am looking for, or if I should just try it anyway, I could vent outside the room. Dealing with air takes a great deal of imagination my stoner mind cannot compute. Feel like an air bender.
 
RuggedWombat

RuggedWombat

Well-Known Member
Hmm yeah if you are already struggling with high humidity then homemade AC would only make it worse. I guess an actual AC unit would help though as it would condition the air and cool simultaneously, though expensive. I'm assuming this room is connected to the actual house. Could you vent to another room even if just the crack under the door? If you can get a space to vent to, then you just need a means of moving the air. So either cool the room itself or remove the hot air and cold air can come in by way of vent or other AC. It'll take a lot you watching a thermometer and sciencing the shit out of this. Experiment with window open. Door open. Just under the crack. Maybe a fan pointing toward the door. Literally try everything and any time it's a bit better stick with that until something gets an even better result. Just change one thing at a time so you know what works. With 75% or more RH that air needs to leave the room with dry air coming in from the HVAC vent. Conditioning that much RH is going to make the room hot as fuck with a dehumidifier. AC unit would be a great option if you have a window, but it'll be costly unless you can get away with only needing to run it a bit. Put the exact same thermometer in your grow room and the adjoining room and compare the conditions. Most likely the adjoining room has cooler AND drier air which is exactly what you need.
 
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medidedicated

medidedicated

Well-Known Member
RuggedWombat said:
Hmm yeah if you are already struggling with high humidity then homemade AC would only make it worse. I guess an actual AC unit would help though as it would condition the air and cool simultaneously, though expensive. I'm assuming this room is connected to the actual house. Could you vent to another room even if just the crack under the door? If you can get a space to vent to, then you just need a means of moving the air. So either cool the room itself or remove the hot air and cold air can come in by way of vent or other AC. It'll take a lot you watching a thermometer and sciencing the shit out of this. Experiment with window open. Door open. Just under the crack. Maybe a fan pointing toward the door. Literally try everything and any time it's a bit better stick with that until something gets an even better result. Just change one thing at a time so you know what works. With 75% or more RH that air needs to leave the room with dry air coming in from the HVAC vent. Conditioning that much RH is going to make the room hot as fuck with a dehumidifier. AC unit would be a great option if you have a window, but it'll be costly unless you can get away with only needing to run it a bit. Put the exact same thermometer in your grow room and the adjoining room and compare the conditions. Most likely the adjoining room has cooler AND drier air which is exactly what you need.
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Yeah it is a house, I guess the tricky part starts with considering the conditions outside the room and outside the house which change. I figured the classic setup just reabsorbed the humid air from plant like the setup is suppose to do. Dehuey covers 4500 square foot but is ok for humid bedroom too.

I can’t really vent to another room, it would be into a open space of 50-60% typical house RH. No smaller room to connect. Air would seep in under door, any cracks/vents exposed.

It wouldn’t take much to build it to exaust out the room outside the house (I know not to vent into attics etc) but managing temp would be harder or easier, will see.

So many mistakes were made last grow that I think I am over thinking it and just need to start it up and see how things go this time but with less mistakes. For sure lots of hygrometer monitoring and air directing.
 
secretmicrogrow420

secretmicrogrow420

Well-Known Member
honestly i recently setup a grow tent in my room i started off venting the air outside but that caused negative pressure in my room and hot air started being sucked in from the attic into my room and made it ultra hot during the day so i just vent the air from my closet into my room and keep a window open with a box fan for air circulation good luck man
 
medidedicated

medidedicated

Well-Known Member
Last run I had a 3x3 light in a 2x2 so it over heated easily but I stay in the room so the dehuey made it too hot for me mostly more likely but was chaotic opening ac vent or door to let cool air from home inside the small room. I feel like dehuey runs less with door shut and plant recirculating into room.

Keeping a controlled enviorment that adds cold ac air to bring temps down or could always be running, I just live with people so it can be hard controlling the thermostat. It isnt consistant, habbits change year after year. Shoot, forget winter is coming up which I just had a fan blow air from outside but it was 90% RH all winter, unusual for snowy states.

I just never setup shop like I am planning for this bedroom but last time I grew in large tent I don’t remember rh even being an issue.
 
TCH

TCH

Well-Known Member
If your dehumidifier is good for 4500sf, then you vent outside, and your tent continues to pull fresh air from inside, it should keep up just fine. You may even put it in the next room so it isn't heating up your tent and lung room. That said, when you vent outside, your temps will drop a bit because you are no longer exhausting warm tent air into the lung room. I cut a 6" hole in the side of my house before this grow and it was the best decision I've made so far. Before next grow, I am going to replace the rigid flex tubing with actual ducting and put in a screen/filter of some sort to keep backflow/bugs etc.. out if the fan is turned off. I will probably also install a Valve as well so I can vent it inside in the winter if I decide to.
 
medidedicated

medidedicated

Well-Known Member
TCH said:
If your dehumidifier is good for 4500sf, then you vent outside, and your tent continues to pull fresh air from inside, it should keep up just fine. You may even put it in the next room so it isn't heating up your tent and lung room. That said, when you vent outside, your temps will drop a bit because you are no longer exhausting warm tent air into the lung room. I cut a 6" hole in the side of my house before this grow and it was the best decision I've made so far. Before next grow, I am going to replace the rigid flex tubing with actual ducting and put in a screen/filter of some sort to keep backflow/bugs etc.. out if the fan is turned off. I will probably also install a Valve as well so I can vent it inside in the winter if I decide to.
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Awesome! I figured there was something with what I have already that could be setup differently. Though it is hard to control enviorment outside my room in spring summer, doors and windows to outside are open often. Part of why I don’t buy a uv fan thing that kills spores.

Lucky for me a window would be right behind the tent that I can rig up some wood and duct tape to seal it and exaust straight outside.

I wonder how the dehuey would do in my situation, I set it to 35% in bedroom which achieves quickly but would probably have to set it to full time mode which may cost more but heck, I hated the heat which even with a properly sized light in tent, I am sure it would benefit plants too. 90F evaporated terpenes notably.

edit actually now I recall it was running all the time anyway with small breaks.
 
TCH

TCH

Well-Known Member
medidedicated said:
Awesome! I figured there was something with what I have already that could be setup differently. Though it is hard to control enviorment outside my room in spring summer, doors and windows to outside are open often. Part of why I don’t buy a uv fan thing that kills spores.

Lucky for me a window would be right behind the tent that I can rig up some wood and duct tape to seal it and exaust straight outside.

I wonder how the dehuey would do in my situation, I set it to 35% in bedroom which achieves quickly but would probably have to set it to full time mode which may cost more but heck, I hated the heat which even with a properly sized light in tent, I am sure it would benefit plants too. 90F evaporated terpenes notably.
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If you keep.it around 50ish% you should be fine. Plenty of airflow in the tent.
 
J

jaboards

Member
medidedicated said:
Yeah it is a house, I guess the tricky part starts with considering the conditions outside the room and outside the house which change. I figured the classic setup just reabsorbed the humid air from plant like the setup is suppose to do. Dehuey covers 4500 square foot but is ok for humid bedroom too.

I can’t really vent to another room, it would be into a open space of 50-60% typical house RH. No smaller room to connect. Air would seep in under door, any cracks/vents exposed.

It wouldn’t take much to build it to exaust out the room outside the house (I know not to vent into attics etc) but managing temp would be harder or easier, will see.

So many mistakes were made last grow that I think I am over thinking it and just need to start it up and see how things go this time but with less mistakes. For sure lots of hygrometer monitoring and air directing.
Click to expand...
Howdy! Why not vent into attic? Moisture?
 
medidedicated

medidedicated

Well-Known Member
jaboards said:
Howdy! Why not vent into attic? Moisture?
Click to expand...
I heard not to do that due to that. Can breed mold. I most likely can only treat the room it is in and have dehuey inside the grow room. I live with people that open doors and windows all summer long otherwise I would try exausting outside of room. Just the other day it was 70%RH due to open doors and was thinking to my self how stressed I would be if I was in mid/late flower.
 
J

jaboards

Member
Y
medidedicated said:
I heard not to do that due to that. Can breed mold. I most likely can only treat the room it is in and have dehuey inside the grow room. I live with people that open doors and windows all summer long otherwise I would try exausting outside of room. Just the other day it was 70%RH due to open doors and was thinking to my self how stressed I would be if I was in mid/late flower.
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I also heard ducting through an attic to a vent to outside is still no Bruneo in some places because your duct will condensate and breed mold. And Yea 70% scares me too. Funny I’m at like 15% rh outside. I put a small dehue in my tent during flower. I also have intake an exhaust fans constantly running and I can still definitely notice a difference in rh with it on compared to off. I placed it right next to the canopy, not high up in my tent cus that’s where my exhaust is. Idk if this helps you hope it does and good luck gromie!
 
K

Kola_Kreator

Well-Known Member
Your grow will improve if you have constant air exchange from outside your room. If you are not supplementing CO2 and you run a sealed room to mitigate rh your plants won't get enough CO2. Setup up constant air exchange but set the fan speed low so the dehu can keep up. Your plants will be perspiring more moisture than your air exchange will be drawing in so your dehu will probably be under less demand than you think. When you said the dehu shut off and the rh shot up to 85% that was the plants perspiration which caused it.
 
medidedicated

medidedicated

Well-Known Member
Kola_Kreator said:
Your grow will improve if you have constant air exchange from outside your room. If you are not supplementing CO2 and you run a sealed room to mitigate rh your plants won't get enough CO2. Setup up constant air exchange but set the fan speed low so the dehu can keep up. Your plants will be perspiring more moisture than your air exchange will be drawing in so your dehu will probably be under less demand than you think. When you said the dehu shut off and the rh shot up to 85% that was the plants perspiration which caused it.
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Ok meaning exaust out of room and have passive intake from outside bedroom? Dehuey inside or outside bedroom? I took a lot of edibles bare with me haha.
 
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