Indoor Greenhorn - 5X5 tent, QB550 LED - cooling Q's

Hi All,
I’m new to this forum. Done a couple fun NL auto grows outdoors this year. Preparing to move indoors with a new to me setup… 5X5 tent with QB550 LED setup, 480 wall watts. I’v got a couple 6" inline fans, one for pumping air in and a nicer one for exhaust that can monitor temps and humidity. this whole tent thing is new to me aside from a couple weeks reading here. My tent is located in a separate garage that can be pretty hot in summer and probably pretty cold in winter. Haven’t spent a winter here yet, so I’ll be finding out. My question is, do you think my fans can handle keeping temps down in the warmer weather and also does the light put off enough heat to keep the temps warm enough during winter? I got the tent assembled today and see it’'s got all sorts of options for fan placement. My thought would be the fresh air would be pumped in via a bottom opening and sucked out the top through either the opening in the ceiling or upper sides. I’ve heard that the QB550 setup can run fairly cool compared to HPS or MH lighting, so I’m figuring I’m probably ok. Just hoping for some feedback to confirm or deny what I’m up to. This is going to be a soil grow. Probably two plants in 7 gallon containers for a start. I’m figuring on keeping both fans outside the tent and running flexible duct in so the fans themselves don’t contribute to the heating issues, at least during warm months. Just plants and lighting inside the tent. Sound lik it should work? Thank you for any input!

The hlg 550 when cranked up can still be pretty hot best to run a fan directly across the heat sink and if you could make a duct to your inline fan sucking ac air from in your house that would be a good way to keep the garage temps out but if you sucks the same air ur exhausting eventually everything will be the same inside and out if you dont have the garage getting fresh air… few dollar at home depot get some 6 inch duct hose and run into the house through a doggy door maybe but u need to have some kind of cooling I have a 6000btu in a 10 x 10 with 4x hlg 600 v2 rspecs and it stay about 80 with the ac set to 75 when I’m in and out the room I’m sure with the door shut it gets downYJZjo.jpeg)


Thanks fano_man,

I live fairly remotely from my neighbors and think I can probably get away with opening the garage occasionally for fresh air. The garage also has some sort of heating/cooling thing built into the wall, but it probably wasn’t designed to be run constantly. I’m also planning to add one or maybe two fans on the inside to move air around. Hoping this will do the trick. House is too far from the garage to easily run any ducting. I guess I’ll find out how good the heating/cooling unit is. Thanks for your suggestions. I’m definitely going to be moving air over the heat sink. Just been reading about the significant temp drops folks are seeing with these setups compared to older. Since this is my first tent grow, I guess there’ll be a few bugs to work out along the way. It’s already begun cooling down here for fall. Maybe my main concern should be about keeping the tent warm enough not cool enough. I have one plant going now. Couple weeks old. I think I’ll use it as a guinea pig. Is unknown genetics. Buddy found a seed and stuck it in a pot I had laying around and it sprouted. If all goes well, then I’ll dig into my super seed stash and really get going. Appreciate the advice!

On your question about heat from lights; All electricity gets converted to heat, even the visible light will turn to infrared from reflecting off of surfaces. Your current lights will give as much heat as a 480 watt space heater. I’m a retired electrician.

During the summer you can mount the driver outside the tent. That’s what I do with my ballast on my cmh

Really depends on what your actual climate is. There are members here that grow in garages year round. They maybe don’t have the most ideal conditions all year, but close enough to make it work. I could never successfully do it where I live though.


The cooling thing obviously dissent coolthe garage because it gets in the 100s that means u got 2 options you get a standalone portable ac no matter how much u think fans will help moving around hot air is still hot air buddy above 480 watts of btus need to be conteracted to get cooling …evaporative coolers …dont work u can get a brand new wall unit at home depot 219 install it and run a box to your tent stand alone unit can be pricey and still need to be exhaust outside the tent… I just switched from 3 400 hids hps to 4 650 watt actual. Draw leds and I feel its hotter now then before with the hids… u have to introduce. Cooled air or u will have a breeding ground for mold in flower please learn from my mistakes there are a few key things that will make or break your grow veg you can handle high heat and high humidity … flower need 75 degrees 80 really max and 60 rh down to 45 at the end to ensure bud rot prevention… theres alot more to growing then you think those things u hear about but isn’t pay mind to are really more important then they seem …more fans will not solve your problem it will waste money it could be saved for an ac… I promise u need an ac it’s a must if your getting in the 100ss I hit 95 my plants wilted I went sfrait to a pawn shop and found a brand new ac for half price and wouldn’t u know it’s a dehumidifier as well


And to answer u r question I bet it will he nice and toasty in there if you want it to be …but if you can atleast run ducts to outside to get fresh outside air instead garage air that will be other option or move the tent inside and exhaust it out a window or in the house


Ok… A few updates… I’m still waiting on the QB, so in the mean time, I replaced my 175 watt MH with a 600 watt MH and the plant seems to be happy for now. Temps did go up from 73 to 85 with right around 60% RH. This is on a 90 degree day outside and the cooling unit for the garage running throughout the day. I have also been opening the garage up to cycle fresh air in at least twice a day, Fall is rapidly approaching, so the good news is it will be cooling down here as we move on into the new season. I’m someplace between Virginia and North Carolina. Pretty mild climate in my region. Right now we’re getting high 80’s low 90’s daytime and mid 60’s at night. I’ve only had the tent running past few days, but for the time being, things look ok, especially compared to my outdoor grows earlier with much higher temps. I’ve got all my heat creating gear outside the tent aside from the MH light. Got a fan sucking that hot air out and another stirring it up inside. Also got another super fan to replace one of my underperforming fans. should be in tomorrow. It can move 350 cfm and the one it’s replacing comes nowhere near that. I’m welcoming the cooler temps. I think they’re going to contribute to making it easier to maintain the tent space as the season moves on. Cooling unit is doing alright for the time being also. There’s room in all of this for me to do some tweaking along the way. I’m also considering running the exhaust outside as you mentioned, fano_man. Just want to do it in a way with minimal visual impact to the exterior of the garage. Maybe something like a dryer exhaust, but up hi on the back where it won’t be noticed. Thanks to all for the advice!

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