HELP! Tent temperatures!!

iGrow420710

Active Member
How are people in Jamaica growing at high temps? ambient temp went down from 25 to 24 and my grow tent when from 31/33 to 28/29 and now the ambient temp dropped to 20 and grow room at 25... but this is all due to outdoor weather... which means my temps will fluctuate due to weather...
 

JSB99

Well-Known Member
How are people in Jamaica growing at high temps? ambient temp went down from 25 to 24 and my grow tent when from 31/33 to 28/29 and now the ambient temp dropped to 20 and grow room at 25... but this is all due to outdoor weather... which means my temps will fluctuate due to weather...
Plants grown outside can handle higher temps because of the massive amount of circulation. Something we can't really match inside.
 

Tim1987

Well-Known Member
How are people in Jamaica growing at high temps? ambient temp went down from 25 to 24 and my grow tent when from 31/33 to 28/29 and now the ambient temp dropped to 20 and grow room at 25... but this is all due to outdoor weather... which means my temps will fluctuate due to weather...
Without aircon.
More air extraction. Simple as that.
You need to be removing the heat faster than its generating.

I run an 8inch inline fan for my extraction.
People say "thats way too much for a 4x4". Well ive got news for them. It isnt!
Fresh air, is the best air.

How big is your space?
What about the cfm of your extraction fan?

Circulation is overrated.
Even the oscillating fans generate thermal heat. (just feel their motor)
This heat just gets blown around the space.
Thats all the oscillating fans do. Blow air around the room.

Either more ventilation, or more extraction is needed.
Id be going with extraction.

:peace:

P.S.
Imo its normal to be a few degrees more, near the top of your tent, than the ambient temperature of the room its in.
Nothing you can really do there.
But closer to the floor can get very close to the room, indeed.

Good luck OP
 
Last edited:

JohnDee

Well-Known Member
Without aircon.
More air extraction. Simple as that.
You need to be removing the heat faster than its generating.

I run an 8inch inline fan for my extraction.
People say "thats way too much for a 4x4". Well ive got news for them. It isnt!
Fresh air, is the best air.

How big is your space?
What about the cfm of your extraction fan?

Circulation is overrated.
Even the oscillating fans generate thermal heat. (just feel their motor)
This heat just gets blown around the space.
Thats all the oscillating fans do. Blow air around the room.

Either more ventilation, or more extraction is needed.
Id be going with extraction.

:peace:
Hi Gentlemen...and you too Tim lol

Just wanted to add something. I have to disagree about the oscillating fan blowing air around...being useless. I also don't think the heat issue is significant...and it equalizes temps in the room. But more importantly it prevents stagnation of air at the leaf. Where exposure to fresh CO2 is crucial for growth.

In a small grow space, perhaps the exhaust fan can move air around enough but even better...is to have air movement.
JD
 

Tim1987

Well-Known Member
Hi Gentlemen...and you too Tim lol

Just wanted to add something. I have to disagree about the oscillating fan blowing air around...being useless. I also don't think the heat issue is significant...and it equalizes temps in the room. But more importantly it prevents stagnation of air at the leaf. Where exposure to fresh CO2 is crucial for growth.

In a small grow space, perhaps the exhaust fan can move air around enough but even better...is to have air movement.
JD
Hi John.

Agreed on the oscillation. Definitely needed. For plant sway etc, to support strong stems, and growth.

But as far as cooling the air in the space goes. Oscillating fans just dont achieve this.

I use oscillating fans as well. They're necessary. Definitely.
But they just cant physically cool the space. They only blow air around.
I have to disagree with you here.

I have 35'C+ days in summer here. With no air conditioning to this day.
Im afraid its just the way it is.
If i need to physically cool my tent in summer. Oscillating fans dont do anything.

Changing from a 6inch extraction fan. To an 8inch extraction fan, made a world of difference.
On my life.

:peace:
 

JohnDee

Well-Known Member
But they just cant physically cool the space. They only blow air around.
My very brief comment about heat distribution kinda addressed that. Keeping hot air from accumulating up around lamps (and bud tips) is enhanced by internal tent air movement. Heat extraction in the form of vented light fixtures would be a real plus too. Transpiration, critical to plant cooling is enhanced through air movement.

I'm not disagreeing that exhaust is crucial...just that air movement is important too.
JD
 

Kingrow1

Well-Known Member
How are people in Jamaica growing at high temps? ambient temp went down from 25 to 24 and my grow tent when from 31/33 to 28/29 and now the ambient temp dropped to 20 and grow room at 25... but this is all due to outdoor weather... which means my temps will fluctuate due to weather...
Ya most of us have houses with some sort of climate control, either get this or grow outside....
 

LowOriginz

Member
I'm wondering if you're providing enough intake to match the fan. Try this, open the bottom port(s), and see how that effects the temps. If it does, then I'll give you a little info on how to turn the vents into sealed passive intakes with a simple filter.
i ended up doing this but how do you turn it into sealed passive intake:weed:
 

Lucky Luke

Well-Known Member
For starters you can grow in the 30s no problem, especially in Veg. Just need constant breeze. Air movement is key. Hell ya can grow in the 40s both in and out. One of the aussie outdoor guys sees a month of low to mid 40's. Nothing wrong with his plants. I saw a week of 40 inside temps late flower and it finished well. Airflow, airflow, airflow. Helps the plants transpire. Like us I spose on a hot day, we fan ourselves to help keep cool.

Is your hyper fan on max? Have you "just" got negative tent pressure? Use 8 inch ducting. Take the hyper fan and place outside the tent. Fans do make heat. Mine sits out side and above the tent.
Are the drivers for the QB inside the tent? If so place them outside.
Run lights at night.
Get rid of that black matt. Black holds heat.
Run lights at night
Run lights at night.
2L milk bottle filled with water and frozen and then placed in an intake does bring the heat down a tad. But just a tad. A tad is sometimes the difference of good from very bad.
 
Last edited:

JSB99

Well-Known Member
i ended up doing this but how do you turn it into sealed passive intake:weed:
Take a length of flexible duct, loop it around to help contain light leaks, if needed, then cap the end with a nylon stocking/pantyhose, to act as a filter. Walmart has $.50 pairs of cheap, black pantyhose that work great. Watch for any wire on the duct that could poke a hole in the nylon.

PSX_20180622_094217.jpg PSX_20180622_094244.jpg
 

LowOriginz

Member
"Stoned I will be" just having morning coffee at the moment.

I use darkroom vents for passive intake. Can get them from Adorama (big NYC online camera supply place)
JD
Take a length of flexible duct, loop it around to help contain light leaks, if needed, then cap the end with a nylon stocking/pantyhose, to act as a filter. Walmart has $.50 pairs of cheap, black pantyhose that work great. Watch for any wire on the duct that could poke a hole in the nylon.

View attachment 4154526 View attachment 4154527
"Grateful i am"
 
Top