Why is my grow tent so hot?
- Thread starter nickwin
- Start date
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Well I've been working all day on rearranging my ventilation setup. I now have the 6" inline outside the tent pulling air through the whole system and blowing it out the window. I really hoped it was going to drop my temp down 5-6 degrees, but it didn't seem to make much of a difference. I've got the light about 18" above my digital thermometer and I am reading 80-82F. With my IR thermo the surface temp of the t-shirts is 88-92F while the surface of the thermometer probe is about 84 (I think its cooler because its white and reflects more light). The surface temp of the reflector hood is about 80-84 on the top and sides. I honestly have no idea why its getting so hot at this point. The only thing I can think of air flow wise is the duct in the first picture on the left seems to be a little restricted. I'm thinking maybe using a 90 degree elbow there would help? I feel like something is seriously wrong though, when people have the same set up with more watts are putting the light a foot closer and are getting temps 8 degrees cooler. WTF?
Dank Hands
Active Member
Take the ducting and plug both sides of your reflector to the ports(without being plugged into the CF or fan). PLug the CF and the fan together pumping hot air at the top of the tent to the outside of the room. If you only have 2 ports in your tent, dont have your reflector plugged into any ducting.
thats all
thats all
You and me both! Ambiant temp in the room is 70-72.
I'm using passive intake, so no intake fan.
I do have more ports I can use, its just everything I read and have been told was that this one fan would be enough to both cool the light and vent the room. I'm kind of confused about what your saying. Wont the room get hotter if I use the same fan with just the CF but without cooling the light?
Dank Hands
Active Member
In my experience, no. As long as air is moving in your tent and its not completely stale, the hot air should rise. I think your problem is suction and will be solved with having the fan directly plugged into the CF. Should vaccum out almost all of the heat from the tent.
Dank Hands
Active Member
Do you know what I mean by having the ducting plugged into the ports and the reflector with no fan involved with the reflector?
Not exactly. Are you saying to just have the reflector by itself, with nothing attached to either port, and have the CF connected directly to the fan with ducting running directly out of the tent?
As you can see in my OP I originally had the fan connected directly to the CF. The fan was pulling air through the CF and blowing it through the light and out of the tent via ducting. Are you saying that this was too much resistance on the fan, and I will get better air flow without going through the light? It seems like the extra CFM from this wouldn't effect the temp as much as as running the air though the light on the way out of the room, but I could be wrong. As I said, I've done a lot a research, but this is my first set up.
Also, the CF does seem to be sucking the hot air away from the ceiling of the tent, its only 72F at the ceiling and on the surface of the CF. Its the radiant heat from the light that seems to be the problem, as the surface temp in the direct light is as high as 92.
Dank Hands
Active Member
well, imo that was your best option if you had no other ports.(2nd best) I would do that, but then plug the reflector into the sides of your tent with the ducting. Your first setup I think didnt work because of the ducting plug ins and bends(it was just reverse from your 2nd setup, but same prob).
Dank Hands
Active Member
so basically with this setup I am describing, most of your reflector heat is in your ducting and in your room that the tent is in. Then the hot air at the top of the tent is sucked out(at the best rate) and pushed outside of your house.
I'm trying to kind of step back here and look at the big picture to figure out what is going on with this. Does it seem normal that the air/surface temp up by the ceiling is only 72 and 18" under the light is in the mid 80s? Is it normal for it to be that much hotter under the light than up by the ceiling?
Dank Hands
Active Member
72 at the ceiling inside the tent or the room the tent is in?
In the actual tent itself
Dank Hands
Active Member
You are gonna need some nice fan action in the tent to blow on the girls/move the air around.
Dank Hands
Active Member
several tiny problems added up= temp problem for you
I do have a circulating fan in there now. Ceiling temp is currently 71, surface temp of the tshirt 18" under the light is reading 88F, and that's with the fan blowing up from the floor across the reflector. Is is possible that I am just getting bad thermo readings? Like maybe the plants will reflect more heat than the tshirt or my thermo probe and therefore will not absorb as much radiant heat?