Dank Hands
Active Member
not sure about your thermometer. If you re-setup your design and wait a while im sure it will improve.
Why is my grow tent so hot?
- Thread starter nickwin
- Start date
Dank Hands
Active Member
in my tent I have the inline fan( setup same as decribed), then i have 2 large stationary fans set on low, then i have 1 small 6in oscillating clip on fan.
I've got one more thing I can try to increase air flow and hopefully reduce temperatures. I am going to put a solid right angle duct piece where the ducting goes out of the tent on the left. As you can see in the picture the flexible ducting gets kind of restricted there. Then I am going to try to shorten the amount of ducting going to the light and try to get it straighter and more stretched out. If that doesn't help I have no idea what to try next.
skunkd0c
Well-Known Member
do you have any pictures of this 1000w hps being cooled by only a 4inch inline fan, 1ft from your plants that sounds crazy me , hope its true and not just hot air lol ?
bigmanc
Well-Known Member
No pics with the temp . . . but my plants wouldnt look the way they do if i had issues. This is my current journal.
https://www.rollitup.org/grow-journals/499458-4-white-rhino-under-1000w.html#post6856016
Tmac4302
Well-Known Member
Yeah, that should increase his CFM and do the trick.
I actually tried that and that alone had little effect on the temp. I left the inline at the end of the system and today worked on streamlining my ducting and that appears to have helped. I've had the light and the and the fan on for about 40 min and I'm getting 77 deg 18" under the light. Thank god lol. The fan seems to be running quieter also which is another plus. I'd love to get my temps down another 2-3 deg, but I think I will be alright how it is.
flowamasta
Well-Known Member
very interesting, im also having troubles with my tent, damn summer 40 degree days!! i like the idea of only having 1 bottom vent open to create negative pressure, i think thats where my problem lies, my zip broke on my tent, so it doesnt seal real well, im using a velcro strip, but there is leaks. i put newspaper over 2 of the 3 vents on the bottom vents, to see if it will create more negative pressure, it kinda makes sense in my head,
i'm using a 6 inch 500cfm centrifugal fan, usually with 6 foot of ducting, blowing through the carbon filter on the outside of the tent, im experimenting at the moment, going down tomoz to look at evap coolers for the room, to bring ambient 28 degree down......hopefully
i'm using a 6 inch 500cfm centrifugal fan, usually with 6 foot of ducting, blowing through the carbon filter on the outside of the tent, im experimenting at the moment, going down tomoz to look at evap coolers for the room, to bring ambient 28 degree down......hopefully
Flowamasta, if you are only using one fan and its blowing air out of the tent and are relying on passive intakes you will always have negative pressure in your tent. Restricting the passive intakes will only decrease your CFM. The bigger the passive intakes the more air flow you will get (up to a certain point at least), and your going to need that CFM!. I got a 550CFM fan for a 105 cubic foot grow tent thinking I'd have no worries but I was wrong.
My problem has been radiant heat from the light. The air temp in my tent is only gets up to around 72-73 (out of direct light), but if I put my thermometer right under the light and have its face pointing at the light it will get up to 80-82F 18" under the light. Surprisingly my reflector only gets up to the high 70's and even the lense feels pretty cool to the touch.
Hey, how did this turn out? I'm having the same problem.. except hotter temps and smaller tent. I have a 20"x36"x60 (25 cubic feet) with a 600w MH light right now in a aircooled tube. I'm using a 190cfm inline fan sitting on top of the tent pulling the air through and a CF on the floor of the tent. So it goes CF > aircooled tube > top of tent > 190 cfm fan. My temps with the light at 75% and about 14 inches above the plant are about 91.
All these threads talk about having big lights and having a cool room, but I don't see how it's possible to get the temp lower.
BlueBalls
Well-Known Member
Sorry for being critical but this is a popular misnomer.
Fans are designed to blow higher amounts of air at moderate pressures.
Blowers are designed to blow moderate amounts of air at higher pressures.
Inline centrifugal fans are blowers. That doesn't mean you can't use them to vacuum.
The vacuum at the intake is the result of the fans designed physical action of blowing.
lordjin
Well-Known Member
You might also want to consider that real plants give off moisture which cools the air somewhat... unlike green tee shirts.
If the suggested solutions are not working for you, here is the last resort. It'll cost you, but it'll work.
Hook your light up to a completely enclosed ducting system. Meaning that you're gonna be giving your light its own atmosphere completely apart from the grow room's atomsphere. A big-ass inline fine is either pushing or pulling the room's air through your light hood (intake opening and exhaust opening through duct -- no sucking grow tent's hot air over hotter bulb). Then you get a second fan and run your filter out another hole for exhaust. Either that or air conditioning. When it comes to managing the heat of an hid, there's no 'magical trick' I'm afraid.
Good luck.
If the suggested solutions are not working for you, here is the last resort. It'll cost you, but it'll work.
Hook your light up to a completely enclosed ducting system. Meaning that you're gonna be giving your light its own atmosphere completely apart from the grow room's atomsphere. A big-ass inline fine is either pushing or pulling the room's air through your light hood (intake opening and exhaust opening through duct -- no sucking grow tent's hot air over hotter bulb). Then you get a second fan and run your filter out another hole for exhaust. Either that or air conditioning. When it comes to managing the heat of an hid, there's no 'magical trick' I'm afraid.
Good luck.
808killahz
Well-Known Member
personally i dont think low to mid 80's is a big deal. So long as temps dont pass 90 degrees you should be fine. Also air temp and radiant temp are two different things. Kinda like if i was going to the beach in 70 degree weather and come home sun burnt. If you reading 72 degrees at the top of the tent and low/mid 80s at the bottom your good. just use that oscilating fan to blow over the plants and your cherry. Or, as lordjin suggested, you can always run your lights on its own cooling system using one fan and your tent exhaust on another fan. that will minimize the bends and allow better effieciency from your fans.
Or you can just run flourescents... lol.
Or you can just run flourescents... lol.
