when growing in sealed room do you need intake/exhaust on building?

Cvntcrusher

Well-Known Member
so i have exhaust in my main room dumping into another room. but i’m wondering…

on my building do i need an intake bringing outside air into the building? and an exhaust bringing all the air inside out?

my thoughts.. this is improbable… i would have bugs and shit getting in through one of the two.. or is there a way around it?

ideas?
 

Cvntcrusher

Well-Known Member
You're dumping hot, humid air back into the room? That's not ideal unless you're running co2. You don't need an intake.
the air dumps into another room. not into the grow room. it also travels about 20ft so it cools significantly before coming back out into the room.

my rh stays at 55% and temps do not go over 80°F
 

lusidghost

Well-Known Member
the air dumps into another room. not into the grow room. it also travels about 20ft so it cools significantly before coming back out into the room.

my rh stays at 55% and temps do not go over 80°F
Your garden is staying better regulated than mine. If it's not affecting anything then I guess you're good. You could probably save a lot on AC / dehumidification if you were venting it outside though.
 

coreywebster

Well-Known Member
Sealed room needs co2 and air conditioning and dehumidifier.
Or its not a sealed room.
Usually an air scrubber too.

If your extracting you need air to replace what your extracting via a passive or active intake , otherwise your not extracting, your creating a small vacuum.

I'd suggest bug screens or filtered active intake
 

Cvntcrusher

Well-Known Member
Sealed room needs co2 and air conditioning and dehumidifier.
Or its not a sealed room.
Usually an air scrubber too.

If your extracting you need air to replace what your extracting via a passive or active intake , otherwise your not extracting, your creating a small vacuum.

I'd suggest bug screens or filtered active intake
hmmmm filtered active intake sounds nice.

but i have all of the above. thank you!
 

Comparator

Well-Known Member
Air exchange once every 1.5hrs during lights out. Once at 6 hrs In during Bloom. 15min.-30min. Depending on fans. Filter air in from the floor of the inside adjacent room that is dehumidified to 50%. Air out threw a scrubber. Both Simotaniously. That's a sealed room BTW.
 

CthreePO

Member
Air exchange once every 1.5hrs during lights out. Once at 6 hrs In during Bloom. 15min.-30min. Depending on fans. Filter air in from the floor of the inside adjacent room that is dehumidified to 50%. Air out threw a scrubber. Both Simotaniously. That's a sealed room BTW.
How you seal the intake?
 

Comparator

Well-Known Member
How you seal the intake?
The Lower intake (sucking in clean, cool, low humidity air) from 6" off a floor w/ a pre-filter circle over the duct that sucks on to an aluminum box with washable filter inside that continues to an inline fan. 6" inline does a 1450sq' room full of plants with an equal 6" inline (out of room on floor) that exhaust threw the big 8" (reducer) 5' scrubber on thr ceiling. With frequent air exchanges during lights off sucking in good, low humidity (50%) air w/o high temps to combat AC thats great. During 12/12 I have one come on half way through flower for 30min. (Stop co2,45min. Prior.). Then co2 pops back on. Doesn't get lower then 650-750ppm in 30min. That keeps the residence from stinking to. If obnoxious then a small 4" full time added to that schedule in a real sealed room should reduce/eliminate odar & provide healthy air environment. Most importantly is to exhaust 15/15 before n after lights on & off. Hope that helps!
Oh, the intake & exhaust port through the scrubber are not really cross breezed so you lose unnoticeable co2 while keeping a fairly neutralized environment. Add a Lil extra duct hose or dim the intake fane by 10% & have min. Negative air pressure. Just a few feet of turned hose kerp the door shutting lightly during air exchanges.
 
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CthreePO

Member
The Lower intake (sucking in clean, cool, low humidity air) from 6" off a floor w/ a pre-filter circle over the duct that sucks on to an aluminum box with washable filter inside that continues to an inline fan. 6" inline does a 1450sq' room full of plants with an equal 6" inline (out of room on floor) that exhaust threw the big 8" (reducer) 5' scrubber on thr ceiling. With frequent air exchanges during lights off sucking in good, low humidity (50%) air w/o high temps to combat AC thats great. During 12/12 I have one come on half way through flower for 30min. (Stop co2,45min. Prior.). Then co2 pops back on. Doesn't get lower then 650-750ppm in 30min. That keeps the residence from stinking to. If obnoxious then a small 4" full time added to that schedule in a real sealed room should reduce/eliminate odar & provide healthy air environment. Most importantly is to exhaust 15/15 before n after lights on & off. Hope that helps!
Oh, the intake & exhaust port through the scrubber are not really cross breezed so you lose unnoticeable co2 while keeping a fairly neutralized environment. Add a Lil extra duct hose or dim the intake fane by 10% & have min. Negative air pressure. Just a few feet of turned hose kerp the door shutting lightly during air exchanges.
Thats some serious grow space
 

xox

Well-Known Member
im not sure what everyone else does, however i exhaust the whole room once per light cycle when the lights are off. its on a timer that turns on a 4" fan with a carbon filter that exhausts directly outside the building. as for intake the room is so well sealed that i simply have a passive intake that has a damper on a spring.
 

Comparator

Well-Known Member
im not sure what everyone else does, however i exhaust the whole room once per light cycle when the lights are off. its on a timer that turns on a 4" fan with a carbon filter that exhausts directly outside the building. as for intake the room is so well sealed that i simply have a passive intake that has a damper on a spring.
I see, so rather then semi neg. you have a neutralizer vent. Have a filter prior to that?
Exhausting entire time lights out or once? How long that once if it is once? By programming in 30min. Exhaust 6-7 hrs in and the timer shuts co2 down 45min. Early. Thats 1.25hr hrs the Co2 is off, staring off at 1250-1500ppm. It's also a min.second feed, that may keep the levels from plummeting. But mines comfortable at average of 600-750ppm the lowest for a few min. Thae most detrimental think to air exchange is at lights on n off! 30min. Each.
 

xox

Well-Known Member
I see, so rather then semi neg. you have a neutralizer vent. Have a filter prior to that?
Exhausting entire time lights out or once? How long that once if it is once? By programming in 30min. Exhaust 6-7 hrs in and the timer shuts co2 down 45min. Early. Thats 1.25hr hrs the Co2 is off, staring off at 1250-1500ppm. It's also a min.second feed, that may keep the levels from plummeting. But mines comfortable at average of 600-750ppm the lowest for a few min. Thae most detrimental think to air exchange is at lights on n off! 30min. Each.
no i dont have a prefilter on the intake because its not taking air from outside the building just air from outside the sealed room. yes it is on a timer i just let it run for an hour it clears the room. im also not using bottled co2 i run a natural gas co2 burner. my co2 doesn't run on a timer it uses a photo censor. i run my co2 at 1500ppm.
 

Comparator

Well-Known Member
no i dont have a prefilter on the intake because its not taking air from outside the building just air from outside the sealed room. yes it is on a timer i just let it run for an hour it clears the room. im also not using bottled co2 i run a natural gas co2 burner. my co2 doesn't run on a timer it uses a photo censor. i run my co2 at 1500ppm.
A circular charcoal screen over the intake duct & a 10"x12" aluminum box with removable top and a diagonal, washable filter is key. Anything entering the room should be filtered. You don't have to exhaust once during lights on, I just recommend to reduce odar & to provide fresh air half way through the 12/12. During lights on + off, you Need to vent/air exchange. During lights out you should a few times.
 

Mont@n@

Well-Known Member
Hi Op, in late bloom humidity is a big problem for us pot growers and the way to control it is to use a dehumidifier/sealed/co2 room or intake from inside/ exhaust to outside combo to control it.

My room 5.7x5.7 used to be a hybrid of both. Both of my intake and exhaust has a zone damper to seal them. They where controlled by a growtronix system to open during lights out if humidity goes above 70% and during lights on when co2 ppm drops below 300ppm comes on until it reaches 700ppm. It’s possible but a little pricy.

Happy growing
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FlowerPower88

Well-Known Member
So say you have a completely sealed room, you have ac/heat coming in via an air handler, CO2 coming in from tanks or a burner (let’s say tanks), and you have a dehumidifier removing water. So you have air coming in to a sealed space, no air going out, what stops the room from pressurizing, or is that not a problem?
 
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