potential heat issues

[loolagigi]

i have a 5x5x8 closet i am vegging and flowering in. i use a cabinet in the closet to veg in, and use the rest of the closet to flower. i have a 465 cage fan pulling air from the room through the cooltubes. as of now i only have a 4" ac line that is an intake, but only runs when the house ac is on. i have had the cabinet running and temps would stay about 71-73. then i turned on my hps today and it went up to 84. i still have another 400 watt hps to make...when i plug that in i can only imagine the heat will rise some. i do not have a circular/oscilating fan in the closet yet. the veg cabinet has intake/exzaust, and a oscilating fan only. so i figure i buy a oscilating fan for the closet...what am i ganna knock off? 2 degrees maybe? i am pretty sure i am ganna have a heat problem. now i do not yet have a intake other than the 4" a/c line that only blows cool air when the ac is on. its been cooler here, so the ac has not been running much. any ideas? Loola

 

[2Dog]

I really wish I could help you more. I keep things very simple..I only grow indoors during winter so I dont have heat issues...I do keep lots of fans going...one actually in thew window bringing in cold air if needed or just planted in front of the girls. one thing to keep in mind is that outside they grow in 100+ degrees, so lets say it does get to 86 is that really a huge deal if they are hydrated and not weak babies? the guys will have lots of input.

 

[loolagigi]

thanks for taking the time 2dog.

 

[clanchattan]

window unit a/c in the nearest window. make a manifold out of cardboard and duct tape. run duct between window a/c and cool tube and omit the house a/c. most of the new window units have thermostats that you can set so it will cycle on and off with your grow rooms temp, not the whole house thermo. or stick it on a timer and play with it till your temps are where you want them.

 

[loolagigi]

window unit a/c in the nearest window. make a manifold out of cardboard and duct tape. run duct between window a/c and cool tube and omit the house a/c. most of the new window units have thermostats that you can set so it will cycle on and off with your grow rooms temp, not the whole house thermo. or stick it on a timer and play with it till your temps are where you want them.

not an option....i have a window, and a window unit, but the window is on the other side of the room. the unit is not in right now as we have not needed it. my wife keeps the central air on 72!

 

[Locked]

I wish I cld help but I am like 2dog...If it gets warm I crack a window...in the summer I battled the heat but never really controlled it...plenty of days it got well over 90 in the tents...I had the ac blasting in the house...that is one of the reasons I am taking a break this summer...

 

[monkeybusiness]

The cooltube you are using, is it homemade? And if so, how wide is the glass? 4"? If it's a bread bake tube I'm not sure it can pull enough air through it for a 400 watt. I know i've read where people use them for 400 watt lights but i always wondered how efficient they were. Physics seems to contradict a strong cooling effect.

And when you say it's a 465 fan, what kind of fan is it? The duct fans that come from home depot and such are really just booster fans and not meant for moving that kind of air.

 

[loolagigi]

The cooltube you are using, is it homemade? And if so, how wide is the glass? 4"? If it's a bread bake tube I'm not sure it can pull enough air through it for a 400 watt. I know i've read where people use them for 400 watt lights but i always wondered how efficient they were. Physics seems to contradict a strong cooling effect.

And when you say it's a 465 fan, what kind of fan is it? The duct fans that come from home depot and such are really just booster fans and not meant for moving that kind of air.

i have used the bake a round pyrex glass tube with a 400 hortilux before with no probs....the 465 cage fan is a squirell cage fan that i baught from my old hydro shop.

 

[monkeybusiness]

i have used the bake a round pyrex glass tube with a 400 hortilux before with no probs....the 465 cage fan is a squirell cage fan that i baught from my old hydro shop.

So sounds like the fan is just fine but the pyrex tube I'd be suspect about. When you used it before without problems was it a time of year when you were running the a/c? Seems to me even if i had a separate exhaust system, but it was only a 4" outtake vent, i would worry it couldn't handle a 25 square foot room efficiently enough. The fact that it isn't a separate system but instead is a part of cooling the hot light system makes me really suspect it can't handle what you're asking from it. Seems like if it was doing it's job the room wouldn't shoot up 10+ degrees from a simple 400 watt that's being air cooled. And pulling through 2 400 watt pyrex tubes is certainly a lot of hot air to move in a small tube.
Just my thoughts
However it works out, good luck!

 

[loolagigi]

So sounds like the fan is just fine but the pyrex tube I'd be suspect about. When you used it before without problems was it a time of year when you were running the a/c? Seems to me even if i had a separate exhaust system, but it was only a 4" outtake vent, i would worry it couldn't handle a 25 square foot room efficiently enough. The fact that it isn't a separate system but instead is a part of cooling the hot light system makes me really suspect it can't handle what you're asking from it. Seems like if it was doing it's job the room wouldn't shoot up 10+ degrees from a simple 400 watt that's being air cooled. And pulling through 2 400 watt pyrex tubes is certainly a lot of hot air to move in a small tube.
Just my thoughts
However it works out, good luck!

yeah, i really need to do some thunking. ill get back to you guys later and see what i can come up with. Loola

 

[loolagigi]

i just thought. my cooltube is 4" but i have a 4x3" reducer on the end of the cooltube that the room air has to travel through....so the hot air from the room is acuallt getting sucked out of a 3" hole thats increased to 4". maybe i need to get rid the reducer and see if the 4" inlet will help.

i also understand i still need a intake and a oscilating fan. im sure that will help. also, would you recommend a passive intake or active? and how big should i make it?

 

[loolagigi]

thinking 2 of these might work for intake. change xx to tt...hxxp://www.geeks.com/details.asp?invtid=CASEFAN-140MM&cat=FAN

 

[The Hemp Goddess]

I have a couple of questions. Is your only inlet a 4" that is connected to your AC? If so, you really have no inlet when the AC is not running. Where is the cooltube pulling air from? Is one end of the tube just open or does it have ducting?

I would get rid of the reducer--a 4" hole is 50% larger than a 3" hole.

 

[loolagigi]

I have a couple of questions. Is your only inlet a 4" that is connected to your AC? If so, you really have no inlet when the AC is not running. Where is the cooltube pulling air from? Is one end of the tube just open or does it have ducting?

I would get rid of the reducer--a 4" hole is 50% larger than a 3" hole.

yes my only inlet is the 4" a/c line that is only usable when ac runs. the 465 squrell cage fan sucks air from the room through the 2 cooltube and has about 5' of insulated ducting up through the cieling.

 

[screwdriver]

Is 465 the model number or the amount of flow rate in cfm?
How are the cool tubes arranged? One after the other or split from two different places off the main duct?
The oscillating fan probably won't help with the temp at all if you just blowing around the hot air.
Are you adding a third 400 watt light and cooltube in your setup or just turning on the second?

 

[The Hemp Goddess]

I would recommend some passive intakes near the floor. Put some ducting on the intake side of the cooltube and run the ducting to the floor near one of the passive intakes. The temp of the air near the floor will be quite a bit less than the temps at the level of the light.

 

[loolagigi]

I would recommend some passive intakes near the floor. Put some ducting on the intake side of the cooltube and run the ducting to the floor near one of the passive intakes. The temp of the air near the floor will be quite a bit less than the temps at the level of the light.

so a passive intake with ducting into one side of the cooltube and the other side sucked out? thats ganna be alot of ducting...and probably diminish my fan power. and then another passive intake to allow cooler air into the bottom of that cab?
my cooltubes run parrelel to one another about 2' in between. so i will have a small piece of ducting between the 2. what else?.....um...
im ganna try a 4x6" passive intake just into the room and see what happens. HG i see what you meen by using cooler air to go into cooltube and then out....but the way my room was made i might have a problem with that. i would have to use a lot of ducting and it will probably look like crap. the intake wall is on the other side of the inlet on the cooltubes.

 

[dinkiefeet]

hello all. can confirm what 2dog says about temps, my last grow i had huge probs with temp, highest was 111.7 then on a night it would drop to low of 64.8 still got very healthy harvest of strong potent bud so would not worry too much just keep well watered. if possible put the water u will use in the same hot enviroment as girls otherwise cold water on hot plant could stress them.

 

[loolagigi]

Is 465 the model number or the amount of flow rate in cfm?
How are the cool tubes arranged? One after the other or split from two different places off the main duct?
The oscillating fan probably won't help with the temp at all if you just blowing around the hot air.
Are you adding a third 400 watt light and cooltube in your setup or just turning on the second?

i am adding another cooltube.....and they will be "strapped together with a small piece of ducting between.

 

[stinkyelements]

Hey yea wish I could help more but my setup is a little more simple, I do have a hard time keeping temps at 80 with the hps but an oscillating fan in the closet to pull cool air in and sometimes leave a window open in the room the closet is in usually helps, so i think an oscillating fan may help a good bit. Be patient take your time i think you'll get it going good dont be too woried.