Ventilation heat problem s

If someone is doing something similar I sure would appreciate some help. I have a 3x3 tent with 300 w LED .with a duct fan exhaust into another tent witch is 5x5 with a 600 wat LED And a 440cfm extraction fan and carbon filter that takes all of the air outside. The fresh air comes in the bottom of the 3x3 with passive air inlet from other rooms in my house…I cannot seem to get the temp below 81degrees …do I need a bigger extraction fan?? Will this not work the way I’m doing it??.. any help would be highly appreciated

I don’t have that set up, but want to say, I don’t think you have heat problems, I do fine at 81 degrees. If you get above 85, that’s out of most growers comfy zone. Unless you already have problems? What’s your 24 hour high temp?

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Maybe around 85 degrees…I always keep it under 77degrees… maybe I’m confused?

Not sure of the time the lights are on, but maybe the lights could be on during the night instead of the day??

Also, how’s the temps in the room Where the tents are?

Maybe hang duct from an AC vent to near the Intake.

I’ve already have the lights on at night… maybe I’m confused but I know everything I’ve read from bergmans lab or anywhere else that the temp should never exceed 77degrees. When I
Turn on the exhaust fan in the 5x5 it maybe brings down the temp in the 3x3 by maybe 2 or 3 degrees…room temp around 74degrees…

My auto are around 80 to 81 degrees

I’m afraid even if it’s at 81 I live in a state where summer is just getting ready to start and if I can’t get the temp down now what am I gonna do in the next 3 month?..

I was having similar problem I lowered the temp in the grow room a little at a time until I remained at a constant 75 in the tent. My temp in the grow room has its own heat and air unit just for that room. I have it set at 66 right now and my day time temp in the tents stay at 75 to 76 during the heat of the day and usually around 70 to 68 at night. My plants seem to like it.

I recently started using filters a size bigger than my fans, and an adapter. I had a tough time keeping heat down, and I noticed when I had the filters disconnected when my plants were seedlings and didn’t smell, my fans moved much more air, and cooled better. The owner of my local grow store recommended I use 6" filters, even though I had 4" fans. It really did help a lot, there’s no smell, and the fans work as if there’s no resistance at all.

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Information applies more to hid lighting. When you run leds you don’t have all of the infrared light to heat leaves. Therefore running canopy temps a little higher helps keep leaf surface temp a little higher, and that keeps transpiration rates up.

Your best bet would probably be to get them independent ventilation systems. What you have now is essentially preheating your intake air and depleting co2 levels for the second larger tent. If you want to continue to ventilate both outside, you can install a Y on current discharge.

FWIW, I am also user of oversized filter. The flange size doesn’t neccesarily have to be larger, but get significantly higher cfm rating than you need.

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Thanks for the info and I agree I’m heading out to get an independent ventilation system for the 3x3 the Y is a good idea that sounds more controllable… thanks for the heat tip also I’ve been stressing about it hitting 80…

I run temps up to 85 degrees with no issues and the House AC doesn’t help on this side of the house. I have had temps hit will past 105 degrees. So I bought a window ac to face into the tent and heat issues are down. :+1:

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