Feeding A/C into tent?

I have a 4x4 tent that runs hotter than I’d like. It sits in a grow room that is at a constant 75F. I have an exhaust fan exchanging the air ~twice a minute, but the canopy is at 84F. The filter/fan is at the top of the tent.

So, my inlet fan is very close to the floor pushing ambient air into the tent. I’m strongly considering moving my inlet fan / hose to the output of my window A/C unit. Is anyone else doing something similar? Are their any caveats I should know about? I’ll also move my evaporative humidifier so that it blows in the direction of the inlet fan opening.

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Nice in theory but it might be a bit much. i don’t have exp. with tent grow @Countryboyjvd1971 is very knowledgeable with ventilation and HVAC you might ask him…

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You can definitely do that or lower temperature in room a few more degrees so your tent cools of a bit also ?

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@Countryboyjvd1971 - I have my outer room temp right where I want it at ~75F. My problem is that my tent temp is 6-7 degrees warmer than I’d like.

I won’t be able to get to it until Tuesday evening, but I’m going to move the inlet to the A/C unit for a few hours to see what happens…

I’d like to be in a situation where it’s too cool and I can work to make it warmer. :smile:

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New at this but my plants did every bit of their veg time at 84-86 F with the lights on and hung around 78 with the lights off. RH was consistent at under 40 %. They did fine even though humidity is recommended to be higher during veg and temps lower by several degrees. I couldn’t get it any cooler and so decided to go with it since the plants seemed to be doing well. Knew I had to get temps under control as the WW autos were already late going into flower, probably from being fimmed and topped. Did the bidding thing on the site that shall not be named, and won 2 900 watt Meizhi LED lights and while waiting the WW’s went into flower and about 15 days later the gold leaf went into flower with lights on 14/10. Got the LEDs up and with tent closed up only going up to 84 steady throughout the day with the lights on and humidity is a tad higher at around 41 %. With the HPS light and the tent closed up with all the fans and exhaust vents running it was still climbing to 94-96. I have a 4 x 4 by 81 inches tent. I know I don’t have the ideal conditions but it is what it is. I did the best I could under the circumstances and I think I will have good yield if something bad doesn’t happen between now and harvest. I think most of us have more than one environmental limitation and temp was mine. I chose to keep them growing at less than optimal conditions and we shall see what happens. :slight_smile:

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Your story is very much like my story regarding temp and rh. My 1 plant :disappointed_relieved: seems to be thriving, but I’m going to continue to try and get my numbers where they should be.

All tuning and tweaking for this and future grows. :smile: It’s almost like a challenge. I’m enjoying it.

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@FreakyDeekie, I have the same issue. I’m hotter than that. One day it was 115 degrees and humidity at 200%.LOL. Not joking. My plants are doing pretty good. I water every day and I’m using miracle-gro moisture-control soil. I think its fairly new. Hey… it is working right? I have a post called Almost 3 weeks in. This is a mystery grow. I’ll be updating the post in a few days. Well anyway, I wish the best for you!

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Hey There happy Camper,
I was just looking at the new post and saw yours. I am doing exactly that with my ac unit and intake fan. here is a pic. Good luck.
D

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Hey guys just wanted to share this
I found my tents at 100 degrees yesterday
I have Ac in room haven’t had the need to run it all season until yesterday
Anyway I tuned it on and cooled room down to 70 degrees now my tents are running at 82 with all my lights on 2 1000 watt cob and two 400 watt cob fixtures in one tent
And 4 300watt leds fixtures in other tent


The key with these portable units is having the two hose venting for the condensor coil this pulls air in to cool Ac unit and exhausts the hot air back out
So I advise all who purchase a portable unit to buy one with the two vents
The single hose type uses room air to cool condensor making then less efficient and in my experience as a HVAC tech unless you direct the cool air where. You need it it just gets pulled out of room
Just my thoughts
Also you need to size units properly for the heat load generated I have 12000 but fir a 6x12 space
Which if Ac was sized to room would be around a 5-6000 but range
If Ac is too small it will just run constantly and cost more in electric just a FYI

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My previous thought was to hook up my tent inlet fan to the output of the A/C unit. But I’ve reconsidered b/c the A/C unit cycles, so one minute I’d be pushing in 50F air, and the next 75F air. I’ll just lower the room temp from 74F to 70F and in affect lower my tent temp by the same 4 degrees. The battle continues… :wink: .

Soon enough I’ll be able to pull the A/C unit out and put a fan like THIS in the window!

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Using CO2 will greatly increase the plants ability to tolerate heat as well. Think of it like a dog panting to cool itself.
I personally use 2 Exhale 365 CO2 bags in my 4x4, and my plants thrive at around 80°- 85°F. Filling tanks can get pretty pricey! You can also find how to build a simple and inexpensive CO2 generator on YouTube.
I also piped A/C from the central heat and A/C vent using just standard ducting, and added a small booster fan to help pull in over to the tent. The only problem is the ducting isn’t insulated, so there’s alot of cooling lost in transit. However I have to keep the temperature set at a constant 70°F to maintain an 80°- 85°F temperature in the tent. That can get costly too! Running the lights at night helps alot though, since it’s obviously much cooler to start and it’s also off peak hours for the most part.
Point is there are less expensive options than spending several hundred on A/C if you think outside the box a little bit.