Climate control strategy

Hello everyone!!! This is my first grow, at this. I have a 4x4x7 tent. I set up in a room that is probably 13x10. The room has one window. I’m on north-east-coast climate. I originally set up a my grow tent with an ac infinity 6" exhaust fan with a carbon filter to extract the hot air out the tent. I am running this across the top. The air is being pushed out the window thru a duct tubing. I had a spike in temperature recently when i increased the light on my seedlings by 30% intensity which its obiously generating more heat and making it difficult to maintain tent under 80°.
So i pondered with the idea that if I added another fan to push air in, with an air intake" fan already in place. Then logically it would bring cooler air inside the tent and staying within my triggers. It’ll be a snap! Easy peasy 123…
Errrrr! I was wrong! I feel like i wasted 200 dollars in fans and filter, for hardly any notable changes and if any I can replicate the same results with what im already working with. So It makes hardly no difference. Yes, I was running fresh air in and air out constantly however maintaining temperature wasn’t easy i had to open and air out the tent frequently just to get the temps to lower inside grow room.
So then i thought that adding an air-conditioning unit is the solution to this issue for sure! I added a stand up air conditioner inside the room so that it systymatically and symutaniously drops the tents temps making the tent temperature optimum for the lil ladies and the set up in my opinion is complete or so i thought it was.
Shortly after i realized that the second fan never made any difference. The air conditioning made all the difference!! The 4" intake fan and 6" exhaust fan running constantly
and simultaneously really didnt impact temperature much at all. i figured why do i need to waste extra money on energy without good results and in my opinion hardly any changes oddly enough occured. What it does help with is the amount of times that the air in the tent is constantly being renewed. It took me days later of testing different scenerios for me to realize that adding the 2nd fan never changed inside temp. much at all and again its constantly running… Just didn’t make sense. I removed the fanand tried it now with only air-conditioning and one small oscillating fan for the leaves to chill and the 6" exhaust fan t6 plus a humidifier.
Who has any suggestions on stable climate instruments and devices to stabilize and maintain a hot environment comfortable for the lil ladies.! Thanks for any and all advice is appreciated :pray: Happy Growing!! :blush:

@The_Chef @


Hey @Graysin perhaps you know something that can help me some. It would be greatly appreciated!

I reread this and i found my mistake. i wasn’t getting the results i was searching for because my problem is the size :upside_down_face: I bought a 4" instead of a 6" to match.

Fan and filter reboxed and shipped back for an exchange to a 6"er!

Happy Growing :blush:

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One thing i did notice is that your ac unit isnt a dual hose unit so your gonna be blowing some hot exhaust air in with the ac. Not a big deal but that will attribute to your heat issue. Unfortunately the dual unit ac units are $300-$500 but i have one in my flower tent and kt work like a dream dropping temps as low as 60 degrees. My advice to you would be to move your light drivers outside your tent and if possible you might have better luck with the ac unit in the tent

All right bro. Take a deep breath and exhale. We’re gonna start from the beginning with your setup. I’ll start with this pic. What contraption is this? Intake?

Lmao!! Its pushing air in, no?? “air intake”?? I was trying diffent places for it and that was my 2nd spot i tried especially because air would circulate better inside since the exhaust is opposing it but on upper part of tent.

I also thought if i didnt add duct tubing it would increase the amount of power it pulls out air

I’ve seen people do this set but on the cieling of the tent fan first then carbon filter right ontop with any duct tape or choking round clamps for air escape

Ok so lets dismantle that :rofl:

Your intake should be pulling in the room air unrestricted. That carbon filter should be on your exhaust fan.

Is that floor AC unit venting outside?


There’s nothing wrong with the placement of your intake. You don’t need that carbon filter on it. That’s where I have my intake


I sent it back already. Im opting for a 6" ac fan instead of that 4"inch in the pic.

Is the carbon filter there a terrible idea? I thought a carbon filter there would scrub the air from my room of the smell later on. But i think i need to put the filter inside the carbon filter instead of outside, i think.


Yes sir ac outside ventilation

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The carbon filter is for your exhaust when removing the air from your tent to help with the smell. Lol


Let the AC cool the room. Once you get the room temps down the intake will pull that cooler air in to help lower the temps.


So with the lights off in my tent, duct fans running, the environment inside the tent basically matches my basement where it’s located. With the lights on, I’m about 10 degrees hotter and 10% drier. I can influence it a little bit with the fan speed, but that’s mostly useful for keeping some of the heat in when it’s cold, by slowing them down.

Being in my cool basement, and not growing indoors during the summer, allows me to save on the AC. If you are going to grow indoors in the summer, AC is just going to be requirement.

I do use a carbon filter on my intake, it’s probably overkill but in my mind I’d be sweeping mold spores or other baddies into my tent if I didn’t have it.


Wait in my head this makes sense but i guess im wrong. Can i explain anyway. If that carbon filter is attached to the fan, arrow opposing filter. Would that filter clean the air that escapes the tent? I dont know because this is my first grow but doesn’t the area outside your tent reak of bud? However, that filter should be inside the carbon filter. But its overkill for some. But i think for others that are concerned with how powerful that scent is its a plus. I assume.

Yes i knew some people use it this way. Does it help at all with the odor?

@THC73 My exhaust fan is larger than my intake, and it exhausts more air then I take in, which creates negative pressure (the tent “sucks in”). No smell escapes if I have the tent doors closed.

On the intake side, it’s probably not doing anything for the smell. But I do want something to filter the intake air. Could probably get away with something that was designed more for home HVAC than weed, but, I was already shopping at the weed store so…


I had a 4"intake and a 6"exhaust and it would cause that negative pressure so what i did for now is take of intake fan and zip that opening closed so then i open a vent so that air is now suvking in all the air from the AC unit.

By the way check out that 25 lb bag of part a i got for 60 bucks!

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Can you exhaust upwards? Attic?
Horizontal Mounting:
Top of tent (inside tent) Filter (connected OPPOSITE arrow on T6 >Exhaust T6 Arrow pointing OUT OF TENT, out the side window.
Alternatively, but less effective pull on hot air maybe,
Vertical mounting:
Exhaust out top of tent to wherever.
T6 arrow UP
Filter attached (opposite arrow, vertically, in back of tent).

Build a hood (cardboard, tape, and mylar bubble wrap), for Air Conditioning unit and feed directly with 6 inch hose to tent (no power) of 4 inch hose under T4 intake

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Where did you score that bro? :joy:

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You made me do a google search and it paid off big time. I just got A & B , 25lb bags from this place. $99 shipped :joy:

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Yes right after i did a search for part b and i seen the same deal. Even better than what i paid.