Cooling 1800 watts in 100+ climate

So, I am hoping someone here with experience in very warm climates can help me out. I will try to be as thorough as possible, I hope some of you can hang in there with me on this long post and help out. I have my whole flower setup taken down right now, and im setting back up in a few months. So, the setup can easily be changed based on your recommendations.

I have ran this setup for 1 year, and I have seen its ups and downs. Temps in the tent have been 80-95, sometimes 95+. 95 being mid day in the summer. 80 being in the winter. The house does not have Central AC. It gets greasy, but we have a little window unit in the bedroom (not grow room), we deal.

My question(s) is... What would be a good way to improve my temps year round, but especially during the 2 months straight of 100+ days?

I would like to be optimal at 73F or so, never going over 78, even during 100+ temps outside. Running lights at night is not an option (security)
I am open to adding a portable AC, redirecting my air cooling to the attic, or whatever.
I am open to a sealed tent system with CO2 if that is the only real option.
Pulling air from another room in the house would be LAST resort for me. I would really like to avoid it. If I must, then I must. Using extra power (ac) to avoid pulling from other rooms would be preferable.

If I do add a portable AC, maybe I should send it straight in to the tent?
Do I need more cfm to cool those lights?
If I add a portable ac, could i use a smaller window unit? (I also own a 9000btu and 7000 btu). However, I do not want to have more than one window unit in the room. (Security)

My setup is... (15 plants in 3 gallon pots of COCO. Drain to waste style.)

Veg, flower, drying chamber and equipment storage in a 10 x 15 room.
A 4x9x7.5 tent is snug in a side of the room. This is my flowering tent.
Inside the tent is 3 600 watt hps linked with 6 in ducting, connected to a 440 cfm HO can fan. The air running through the lights is pulled from the rest of the room, through the lights in the tent, and back in to the room. (I know this is not optimal, and that is part of my question.)

The exhaust for the room is... a 750 cfm Phresh Filter mounted at the top of the tent, connected to 6 in duct, ran out of the tent and in to the atic. IN the attic that duct connects to a VORTEX 747cfm fan, which has a 5 ft length of duct connected and pointed towards an opening of the attic. (I run my lights during the day to reduce heat sig in the attic.)

I have two 4 inch inline fans for intake to the tent. 1 comes in on the left side, 1 on the right. These tent intakes pull from the 10x15 room the tent is in as well. (Larger intake fans?)

So as for the rest of the room(veg and all) ... I have (4) 4 ft 2 bulb T8s for my mothers, clones, and veg plants. (It gets tight, but I make it work) I occasionally suspend some cfls to add some room for just a week or two.

For my cooling of the room... I have a 12,000 btu window unit. (Backyard window, locked gate, high fences.)

I have oscilating fans all over the place. 1 large in the tent. 4 in the rest of the room.

So there it is.

Any advice is much appreciated.
Much thanks to all who submit answers to the many questions asked on this site.
You all have been a valuable tool over the last 3 years, and def helped more than the text book style reads that are for sale at a book store.

Thanks again.

Wassup Bro - I think i hear you...

Thats a lot to read... and i'm at about a [6] right now. But I'm bored, and looking to help

so, the first thing i think when i hear all that you just said, is that if I were you, I would be exhausting the heat from the LIGHTS into the attic, and recirculating the air in the bedroom, and the tent environment.... your 12,000 BTU (1 ton) AC will work a lot better like that... as it will be able to cool the air in the room, because it will get to cool it several times... its not ideal to be exhausting a lot of air out of the room the tent is in, as the whole room has to fill with new air, that it gets from other rooms, the attic, outside... wherever it can.

If you switch that up, i think temps in the tent will improve a lot... the light heat is the killer... GOTTA exhaust that. Rule of thumb if you DONT exhaust that, is you will need 1 ton of AC for each 1000w of HID you are running... that means in your current setup, you pretty much need to get a second portable 1 ton AC to deal with that alone... but thats in a sealed environment... if you are exhausting 400cfm from that room all the time, even those 2 ac's wont be able to keep the temps down.

so, I would try to get outside air, or attic air as intake for the light duct circuit - and exhaust that into the attic by the window thing you were talking about... then run the carbon filter, and 400cfm fan inside the tent, and exhaust that air into the room... that way, when you open your tent, it will be sucking air in, not letting the smell out - and if there is smell in the room, within a few minutes the tent will use it as intake air, scrub it and exhaust it smelling clean This will make your AC way more efficient, but if you could get another ac in that room, even a 6000 BTU, it would probably still help... if you cant do that, hook up some CO2 and just keep the whole room 10x15 at 1500ppm - your other plants will use it too. This will let your flower plants easily handle 90-95° temps.

Hope that helps!!

on another note, 1800 watts in a large tent is a great plan... I got one of those running right now, and am very happy with the results so far

Thanks for replying bloodshot, quick too. Sorry about the long read, I've been known to ramble on a bit.

I agree I need to redirect that light heat. I found a spot to pull it from in the house after all. My bedroom closet is going to get a 6 inch hole to pull from. The bedroom has a small ac in the window that I can leave on during the hottest days. I was thinking I would put that 440 fan above the hole in the closet, then run that duct into the 10x15 room, through the lights, then put another 440 after the lights, then exhaust either out the window or in to the attic.

I'm thinking that would be better than pulling from the attic?

I want to make sure I am getting you straight with the exhaust suggestion. You are saying exhaust the air from inside the tent out to the 10x15, have it stir around the room a bit, and then taken in to the tent again by the intake. Repeat, repeat, repeat. Right?
That seems to me like that would require me to seal off the room better, and use CO2 (which I am open to). As well as, add another air conditioner (also open to). Perhaps a portable ducted straight in to the tent to help the temp in there a little more?

Yeah man. I am liking the 3 600 for real. I've been tempted to cram a 4th in their, but I know I would have to really get my temps under control first.

If you got time to respond I'de like to hear what you have to say about that. If not, Thanks again.

id say just throw a portable ac in there and run the ducting into the attic. i have a 1000w in a closet 8x4x10 and in summer here it can get to 116 at its worst. i just throw my 9,000 btu portable in the room trun off all exhaust and intake expect the a/c exhaust and just max it out not exactly energy efficient but you said youd rather have the a/c.

Yikes - this is a tough one. You will not be able to reach your desired target temps of 73F, in 100+ temps (27 degree differential) without running a sealed room and supplementing CO2. This is the way for you to go. I know, it's costly, but it is the only way to conquer such a temp differential.

I would stick your veg material in a tent too - squeeze a 4 x 4 along side your other tent. Get a 2 ton split (or more tons, if you can spend it). Use CO2 tanks (way cooler than even water cooled CO2 generators) to supplement CO2. Get a controller to monitor temps and CO2. Route your lights to take in air from another room (yes, you must do this) and exhaust in to yet another room or attic. Run exhaust from both tents into the room. Use either passive intakes, or active intakes breathing in from the room too. Set the split ac up on the outside of the house (they can be attached on the side of the house under an eve or awning or on a slab). Cool and CO2 the shit out of the room housing the tents (approx 65F or less, and 1200ppm CO2 to start). Setup a temp controller in each tent to fire the intake/exhaust fans as needed. Adjust the AC temp, and CO2 concentrations within the room, to get to your desired setting within each tent.

Thanks for the reply Lionsroor

I think after hearing similar idea from a second person I am starting to understand what you and bloodshot have in mind. I like it. Veg tent is a great idea. the room actually has a 10x2x8 closet (weird dimension, i know) that i could close off and turn in to a veg "tent".

I've got one question/concern though.

I am a little worried about setting up a split ac unit being in a rental house. With the outside unit, and from what I understand about the installation, it makes me a little cautious. If this is the only thing that will truley work though, stick to your recommendation. If another way could work though, cheers.

My question is, what is the advantage to the 2 ton split over just adding more cooling with an additional portable two duct ac? That would be the portable ac that allows me to pull in air from outside, and exhaust outside to cool the condensor.

I could upgrade the 1 ton window to a larger unit if needed, as well as add a portable of whatever size. So if MORE than 2 ton of window+portable is needed to equal the 2 ton split, i would prefer to do the more... within reason.

I am guessing the advantage is no loss of CO2 and escape of smell?
How much cooling power would be needed to run the system you described with 1 window and 1 portable ac?

Keep in mind I DID come around on the lighting air cool circuit from another room to the attic, thanks for the smack of the obvious/reality to the face on that btw.

LionsRoor said:

Yikes - this is a tough one. You will not be able to reach your desired target temps of 73F, in 100+ temps (27 degree differential) without running a sealed room and supplementing CO2. This is the way for you to go. I know, it's costly, but it is the only way to conquer such a temp differential.

I would stick your veg material in a tent too - squeeze a 4 x 4 along side your other tent. Get a 2 ton split (or more tons, if you can spend it). Use CO2 tanks (way cooler than even water cooled CO2 generators) to supplement CO2. Get a controller to monitor temps and CO2. Route your lights to take in air from another room (yes, you must do this) and exhaust in to yet another room or attic. Run exhaust from both tents into the room. Use either passive intakes, or active intakes breathing in from the room too. Set the split ac up on the outside of the house (they can be attached on the side of the house under an eve or awning or on a slab). Cool and CO2 the shit out of the room housing the tents (approx 65F or less, and 1200ppm CO2 to start). Setup a temp controller in each tent to fire the intake/exhaust fans as needed. Adjust the AC temp, and CO2 concentrations within the room, to get to your desired setting within each tent.

Click to expand...

a 27 degree difference isn't big at all CO2 sealed tent and an AC are overkill. It's currently 12F outside of my home and yet the inside is a toasty 72F. You're forgetting that houses have WALLS and insulation to separate them from the elements, this isn't astrophysics trying to cool a room.

Portable AC would work easily, just set it up *outside* your tent, and attach some flexible duct to it to run to your tent. You don't want the AC in your tent because window units like that blow out freezing cold air, you want the air to raise a bit in temperature before hitting your plants or they get a huge burst of frigid air and you're causing undue stress to your plants. Not to mention you'd be recirculating air in your tent and the AC unit would smell like ganja 24/7 from pumping the same air through over and over.

I had a 10,000 BTU portable AC in my first apartment and it kept the room at 73F when outside temps were 90+ with ONLY this window unit running to cool a 20x8x8 room. It'll get the job done easily and setup is quick and easy. If you want CO2 you should get that just for additional plant growth, but considering you're in a rental I'd assume you would want less crap laying around that could incriminate you as a grower and get your ass in trouble with the land lords.

Edit: You also would probably need to find a way to remove the temperature sensor from the AC unit and run it to your tent to make sure it's reading the tent's temp and not the room temp outside the tent. Or just do some trial / error to find what settings will keep your temps level.

What's up Exdex?

I hope you are right and I am overreacting over my temp issues.
Given that I was recirculating the heat from 1800 watts hps into my room holding the flower tent, but will soon have it setup properly, I might see that you are right when I set it all back up.

I think I will re setup everything as before but with the light air cool circuit going, and then judge the situation from there. I have a feeling it will make a huge difference.

The co2 is so tempting though because of the fact that I have a 747 fan up nearly all the way sucking out all that just cooled air from my 1 ton window unit. It seems so inefficient.

If the temps are easily under control after this, then I would like to add a 4th 600 hps to the tent. If still easily controlled, go on to co2.

I did a little measuring, and I think I have just enough room to squeeze in a Daystar AC.

I'm sure by the end of the night I'll change my mind once again though.

Co2 is probably a good idea regardless it should help with increased yield as long as you're growing enough plants to justify the cost. Long term a Co2 generator would be a way better idea than tanks but it all depends on the size of your op. Temps shouldn't be that big of an issue, your average house has decent enough insulation to make maintaining 50+ degree differences no problem from external temperatures, especially considering you'll be running a window AC unit into a closed tent maintaining the temps should be a breeze.