Cooling down tent with ac

Discussion in 'Growing Marijuana Indoors' started by Michael4367357, Jun 10, 2019.

  1. Summer is here! Need a little help, I was running a in-line fan from outside into my grow tent all winter with no problems but now with it 80 degrees I no longer can do that. I attached a fan to my window ac to cool things down. Will this work? Do they still get fresh air even though they are going through an ac first? Please see picture, any help is greatly appreciated! [​IMG]

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  2. You should reverse the fan setup to match what the vast majority of people do.
    Use a passive intake to get air from inside your house, then eject hot tent air to the hot outdoors.
    In the limiting case of super high fan speed, the conditions inside the tent will match those outside the tent.
    In practice, even with the highest fan speed, the temp will be higher inside the tent, and the humidity will be lower than your house.
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  3. There actually is no such thing as "cooling;" cooling is the absence of heat. Since you can't add cool you can only exact heat your best bet is just to extract the heat the lights are adding with an exhaust fan. As BK said, use passive intake, crack you vent fan to max and your tent should settle about 5 deg F warmer than the room it is in.
  4. Thanks guys, I set up the exhaust to outside. I have the inline fan on my floor now brining in air from my room instead of outside. I guess I need to make it cooler in my room because the heat actually went up in the tent after reversing it [​IMG]

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  5. Do you have two fans or one? If you have two you are better off with the intake on the AC, like you had it. If you have only 1 fan use it as a exhaust fan.
  6. I have 3 fans, I have an exhaust fan in the tent bringing air out of the tent from the top and then another booster fan hooked up outside of the tent bringing the air outside of my apt, the 3rd fan is being air from inside my room into the tent, hope that makes sense

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  7. Im not talking about circulation fans just duct fans. If you have two ducts go back to how you had but also know the fresh air intake fan inst doing much unless your tent is lot bigger than I think it is.
  8. Looks fine, I dont see any taco leaves or heat burn
  9. I was talking about duct fans, with circulation fans I have 6 total. It’s only 3’ x 2’ x 4’ I think I had this misconception that I need fresh air from outside coming directly into tent. I’ll go to passive intake but during the dark period won’t light get in unless I use ducting as a barrier? Also, why wouldn’t the fresh air intake be doing anything? I need to read up on how air works

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  10. As your duct fan takes air out, it has to be replaced with something so it draws air in. Basically your are pushing in the same air your exhaust fan is pulling in. Idk why you have this many fans in that little tent. I have one duct fan in a tent that is twice as big. Fans have a CFM rating, that number should be equal to about half the size of your tent; meaning you are circulating the total volume of air in your tent every 2 min when the fan is on.

    FYI fans generally can’t make your tent cooler than the room the tent is in.
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  11. With lights on your tent temp will still be higher even using the cold ac house air. Example house air temp 78 degress but with lights on your tent temp is 88 degress due to lights putting off 10 degress higher temp. You need to use direct ac cold air to bring the temps lower if you need it. Keep the intake and exhaust how you just set it up and in addition run a 4 to 6 inch duct tubbing from the front of the ac unit to tent. Attach one end in front of ac unit and stick other end inside the tent. This way when the ac is on the cold air goes into the exhaust tubbing directly into your tent. Pricey leaving ac unit on all the time, but thats why i grow autos in the summer so i can put them outside during the day and only run the ac unit at night when i bring them in. Or you can keep your house temp at a overall lower temp. I bought a small portable ac unit that i use only for my 2 grow tents, that i have tubbing attached to in front of ac unit and split it going to both cabinets.
  12. You are the man, thankyou for the Insight

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  13. #15 Anydawana, Jul 13, 2021
    Last edited: Jul 22, 2021
    Look, if you feel that everything is cooling down, then leave it like this. Just do not forget that the air conditioner gets dirty over time and needs to be cleaned with such a long operation. I don't know if this will affect the growth of grass, but you should know it anyway. By the way, I recently thought of doing something like this myself, but I can't find the time and money to grow it. What do you think, where should I start, and in what ways can I grow grass? I'm just new to this business, but I would be grateful if someone knows more and can share their experience with me :)


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  14. A strong exhaust fan can accomplish most of what AC can, but much cheaper.
    A fast enough exhaust fan speed can cause temp/humidity inside a tent to come close to those right outside the tent.
  15. Hot and humid here for the last couple weeks. I run a 4x4 tent in the spare bedroom with some veg in the closet of that same room. Have had to open up the tent to the room and try to climate control the entire room.
    That has meant running a portable AC and full size dehumidifier 24/7. It hurts bad in the electric bill, but its not only keeping the plants from overheating, but has given me the control to finally chase VPD, usually able to stay fairly close to target.
    Second added bonus is that the dehumidifier is producing about 5 gallons a day of water that measures 8-15 TDS (500 scale).
    All that said, with the climate control and moderate VPD control, getting the best growth I have seen yet, by far. Our weather turns cooler and drier in a couple months, so can dial it way back at that point.

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  16. In my opinion there is one more methods of improving the air what we are breathing . Nowadays every house and office is equipped with air conditioner .
  17. #19 ginawilson, Oct 23, 2021
    Last edited: Oct 25, 2021
    You worry too much about it. Any plant can be grown by keeping it under the air conditioning. This device cleans and cools the air and thus doesn't harm plants or people. I will give an example of my air conditioner and a room with plants. I have a five-room apartment, and one of these rooms is allocated specially for plants. To keep the flowers in good condition, I cool the room using the best domestic air conditioner. Also, on the advice of some experts, I don't open the windows in that room, so as not to harm the plants. So, stop worrying so much about your weed.

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