Air Cooled hoods.... air flow problem?? Please help!

[clowntown]

If you want to play the bigger-dick game, I've recently set up and designed a much larger duct system for a paper recycling plant where this stuff really matters. An extra 45 degree bend here, and an extra there, will effectively render the system useless due to the lost velocity (and thus overall efficiency of the system). These aren't your 115/120V inline centrifugals, but modified three-phase 480V squirrel cage fans sucking literally tons of shredded paper and cardboard particles through 12" ducting.

While I really dig the clean, neat setup of your room (or the room you set up), and while I'm not doubting the efficiency of your hoods, your ductwork sure is inefficient. Are you saying that you designed it to be that inefficient? 'Cuz you could have done that with a speed controller or a smaller fan. To run the same amount of air through that system, you obviously need a larger fan than in a more efficient system. But was that all part of the big plan, to make as inefficient a system as possible and throw a larger fan in as a penis extension?

Maybe you should take that foot out of your mouth first before you sit behind your computer and preach. No matter how great of a weed grower you may be, you can't defy physics.

What, did you think your 10" Can-Fan with an inefficient flow system is some big deal? What, you run 3-6kw and now you're some big-shot, big-timer? Did ya wanna talk down to a little 600w guy? Are you feeling threatened by my education, and feeling the need to attempt to discredit me? Pfft. Please, try again.

(Just to have you know, I have an extremely inefficient duct system in my grow. But I don't go touting it as if it were the best and greatest, and moving air has never been a problem for my 10 feet or so of ducting.)

 

[Budweiser13]

lets be cool fella's and smoke some good herb and try to help each other..................

 

[clowntown]

You're right, Bud, this is useless arguing over nothing. But it is pretty irritating when you have someone with no idea trying to discredit you just because they don't like to be corrected.

I'll be signing off from this thread. Good luck.

 

[Budweiser13]

Hey clown you and grit are talented and can get your shit done. But damn if these threads lately just turn into pissing matches. All you homies should just try and help each other and get high and be happy........Arguing is stress and stress kills.................

 

[Guest]

lmao clown... i do have an 1100 cfm 10" can fan but that runs at a different spot and for somthin besides coolin lights. if you go back and read this here 3k light set up is cooled to perfection using a single 6 inch fan. sorry to get your panties bunched an all but you are pretty far off the mark. i'm a middle aged guy and "big dick contests" as you put it are in my past. i go by what i know and what i've done so take it for what it's worth. some of you younger cats (or dumb ****s as it may be) with an ego trip tend to let yer ego interfere with your learning curve... i don't care much though, carry on as you will :smile:

with regards to Ozymandias15 situation of having trouble making the best of the equip he has on hand i've offered him 2 options that he hasn't tried yet to remedy his prob using the equip he has... running inline as you suggest as the most efficient way is not working and you say my set up is inefficient? are you suggesting that it would run better if set up like ozymandias15's? ....which would be runnin my 6" fan straight into a 4" reducer and string the lights together.....wow. i'd look into gettin a refund on that education clown.

mind tellin me where i've been corrected?

i think i've answered your pm in this post so don't expect a reply.

 

[Mr Celsius]

All that matters is if something works. I'm not taking sides with any person, but with a technique that works well. If you feed air separately, like forty, it just makes sense that heat would not build up as it passes through each hood. While I agree that bends in the duct would reduce efficiency, forty's still works, so it doesn't matter.

I personally will be using forty's system, without bends.

 

[Guest]

All that matters is if something works. I'm not taking sides with any person, but with a technique that works well. If you feed air separately, like forty, it just makes sense that heat would not build up as it passes through each hood. While I agree that bends in the duct would reduce efficiency, forty's still works, so it doesn't matter.

I personally will be using forty's system, without bends.

you're gonna like how well it works... i'm very, very impressed with it. don't worry about the bends comin off the hoods cause they won't hurt flow much at all. reason being is that the overall flow area is much bigger at the hoods than it is at the fan's outlet so the air speed/velocity is much lower there and can make it's way around the bends with ease. for example, if you use a 6" fan to cool 3 hoods with 6" flanges the air comes from a 6" duct but then is spread out over 3 hoods so 18" of flow area... plenty good and not much restriction at all. the flex ducts that come off my hoods are 3' long so a 90 degree over 3' aint hurtin flow much at all if any.

 

[Mr Celsius]

There's no need for bends, seeing as the actual AC part of the hood will be facing the main ducting, creating a straight shot. It seems with the hoods that you are using, you could just rotate them a little and they would also have a straight shot, not effecting the lighting foot print.

Regardless of the minor details, this method is by far the most efficient I've seen so far.

I plan on cool 6 - 1000w HPS's with a Can Fan Max 10" (1000 cfm). The main ducting will be blowing through a center tube with 6 T's (3 on each side) through 3 hoods on each side and from those hoods into another 10" duct and out of the room. In theory each hood should be getting around 160 cfm and each hood is about 6 cubic feet; so we have an air exchange in each hood every 2.25 seconds... I somewhat doubt that much heat will be able to build up in that amount of time. All ducting will be completely smooth interior with reflex for insulation; also all seems and cracks will be covered by metal tape.

 

[Ozymandias15]

Sounds lovely wish i had the space for that kinda set-up in this grow. I've decided that i'm going to swap for cooltubes, since they seem to have much less restricted airflow, and hope that it works! I've just borrowed a 15000btu aircon unit but can still only have 3 of my eight 600 watters on in there... which is rubbish!

 

[yamaha_1fan]

where is the air coming from thats being pulled out of the hoods? Do the hoods have glass? I guess my underlying question is if the room is being AC'ed are you pulling the ACed air out of the room through the lights?

No disrespect here just trying to understand as I have 3 4x12 tables that are going to be running 3 lights per table and am still working on the light cooling

 

[Guest]

There's no need for bends, seeing as the actual AC part of the hood will be facing the main ducting, creating a straight shot. It seems with the hoods that you are using, you could just rotate them a little and they would also have a straight shot, not effecting the lighting foot print.

i considered that when putting it together. rotating the hoods would give it a straight shot when the lights are raised all the way and stationary but the lights wouldn't be able to be lowered without creating more of a bend(s) than what's there now because the lenght of the flex duct would have to be much shorter- 2 tighter 90 bends when the lights are lowered as opposed to one wide radius 90 that doen't change when lowering the lights. i designed it using long ducts (3') coming off the hoods to decrease the radius of the bend and so the lights can be lowered with minimal effect on the ducts. if the wide radius 90 does hurt the flow it aint much...not near enough to offset the benefits when raising/lowering lights is considered. there's no heat problem there

i think the straight shot could work if the intake and exhast plenums were spaced farther apart but that would take up too much space on the ceiling in this case. (less room to hang the scrubber, other lights, etc.)

your set up sounds killer man.. should work great. consider making your center cool air tube oversized, 12" or 14" diameter. this will help even the flow out of each T.

where is the air coming from thats being pulled out of the hoods? Do the hoods have glass? I guess my underlying question is if the room is being AC'ed are you pulling the ACed air out of the room through the lights?

No disrespect here just trying to understand as I have 3 4x12 tables that are going to be running 3 lights per table and am still working on the light cooling

the air is drawn from the basement below the room and is exhausted into a different room. the grow room runs sealed w/c02 so no air is drawn out.

the air is pushed through the lights, not pulled. the main reason is so a plenum can be used to even the flow to each light. a 6" duct comes off the fan then into a long 8" duct with an end cap on the opposite end. 4" ducts come off the side of the 8" duct and through the light hoods. when pulling, the air would take the path of least resistance and make uneven flow. the other reason i like to push air is if there are any small leaks it stays in the room- no smell escapes.

 

[yamaha_1fan]

I see. I didnt read your original post thoroughly. I only saw the black hoses going into one side of the hood and nothing coming out. But now I see and read there IS an in and out of each hood going into the other 8" tube behind the hoods. It was hard to see in the pic.


Thats a cool setup and VERY clean.

 

[Ozymandias15]

Thought that i'd give you guys an update. I've bought 4 twin cooltubes (the ones with 2 bulbs in each reflector) and got the whole thing ducted together. With 4 lights on the temp went down to 27C (down from 33C) but creeps back upto 33 when all 8 are on. I'm going to increase the fan size but the airflow is fantastic with the cooltubes, totally unlike the sealed supernova unit. Pumping all the air up the chimey send a huge amount of soot out of the fireplace upstairs which went unchecked for 8 hours! Anyway the verdict is that cooltubes are fantastic but they don't spread the light so well... just like everyone has always said!

Thanks for the help guys i'll post more when the set-up has been tuned.... including pics

 

[Budweiser13]

Fortygrit could you please make a diagram or do a tutorial on the correct way to setup air cooled lights. I am still confused on the plenum thing. Knowing the correct way to air cool your lights is a big thing in the growroom...

 

[Guest]

Fortygrit could you please make a diagram or do a tutorial on the correct way to setup air cooled lights. I am still confused on the plenum thing. Knowing the correct way to air cool your lights is a big thing in the growroom...

i agree, that would be tits.

 

[simba]

LOL sorry..

yall should look into air stabilizers.

what the hell is that u ask..

well typacly when air is moved etc in contained areas it creates turbulance and then ur air dont move nicely..

however..
if you Stablize the air (from fan) all the air threw ur pipes will flow easier..

what got me on that..
3 things..
1. cars catilitic converter (if u ever guted one u notice ur flow is smother with it)
2. an air handling expert told me i needed to look into stabilizng air threw tubings. (for a Masive Bunker)
3. my grandfathers Bi-pap,, (its ours) ( ilove it for mini air cooling hood)
it has a High Volume/presure blower..
and when cleaning it.. there was a set of Stablilzers (like the Cat)
i forgot to put back in and the flow wasnt there any more..
put back in and Bamo..

but for us how to make it..

if u have a 6" pipe or whatever.. go get corisponiding size pvc (only 12 inches long.
get a few bags of Straight straws.
place them all in there (tight but not to tight) you may have to rig it a lil bit.. it dont mater if the straws on the eges are coverd
(key dry fit them, then place in with glue and layer)

you willl get Stabilized AIr and will be allot easier to bend and not decreess flow etc.. within reason

 

[Budweiser13]

Simba thanks for the input but that is starting to sound even more complicated. fortygrits way is a good way I have heard of it but just dont fully understand it. His picture does not show the whole setup a diagram or more pictures would really help..........

 

[simba]

oh it dont matter what system u use..
air is not stable coming out of a fan..and then put in tubes and bends and then in big areas and slams into walls etc..

take ur hand while your furnace (ac or heat) is on (blower running)
with the Filter plate off.. feel the air right by the inlet on the SQ its so Turbulent.. u can feel air bouncing around..

what i recommended u do after smoking a bowel it takes 10-20 minutes and nothing else can fix turbulence than this LOL if that makes sense..

whether your pulling or pusing air having a stabiliser on the Cold side of the system will make it allow more air to flow threw easier..

especialy if u building a spliting plenum..
all that is a Y box..



but if u have turb air it wont split effeciantly..
if u have stable air u can go from lamp to lamp not y'ed off and still have nice flow even with bends..

but straight shots are great..

heres a pic

 

[Budweiser13]

^ Bump ^ Lots of peeps starting threads lately about light hood cooling. Would be nice if some peeps with HVAC experience could show the correct way to set up air cooled lighting. Lots I dont under stand such as Static pressure, Plenums,exhaust manifolds any body good with air ducting.........

 

[Budweiser13]

Did some searching good link...http://www.icmag.com/ic/showthread.php?t=34761&page=3&pp=15.....