.: A Couple Questions to be answered plz :. :P got drawings too

ok i have some questions here, im planning on ordering parts for my grow soon.

Questions:

1- im planning on having a sealed room thats 10 x 10 x 10. how much cfm does my exhaust needs to go throu the 4x 600w hps and corners and thru the carbon scrubber for best results, like no smell.

2- do i need an intake? im confused about this. in one of the drawings i drew a scrubber + fan in the sealed room, and i was thinking is it possible for me to buy a big powerful exhaust fan that can intake/exhaust at the same time.. like open a whole at the bottom with ducting to get fresh air from the other room while its scrubbing also.

or would it be best if i just have open holes at the bottom like 4-6 holes and let it pull air from the other side of the sealed room.

3- how big should my carbon scrubber be with the cfm size??

4- do i really need Co2 if its sealed? even if its pulling air from another room in the house or in the same room its in?? will they still live?
or would it be best if i pull air from the outside into the sealed room..
or just get a damn Co2 tank / control XD

hmm, thats all i can think of for now. ill ask more later if anything.. please help!!

Help Bump!!

I'm only new to this myself, but I think you want to fan to pull the air through, not to push it. So in that set-up, you would want the fan here-ish.
View attachment 1534312
Also, you want to cut down on bends, so moving the carbon filter like that helps.

I made a cfm calculator from post#6 here http://boards.cannabis.com/indoor-growing/132514-noobs-guide-growroom-set-up-work-progress.html
but it's giving me silly numbers for just 1 600w. (6000 cfm)
The reason for that is: 10*10*10 room needs 200cfm to clear the air in 5 mins.
the length of ducting(calculator adds 10% for each foot, 5' each way + 4' in bends is +140%; brings us to 480cfm)
plus a carbon filter(calc multiplies by 1.3) brings us to 624cfm.

the problem is the bends, calculator multiplies by 1.5 per 90 degree, which is 4*1.5*624cfm=3744cfm ( for a 400w. a single 600w is *1.3, which brings it too 4680cfm.

If I was you, I would use 3 fans, one with a carbon filter, which vents the room, around 390 cfm(using 5' of ducting in a straight line.
and two smaller fans taking air from outside, cooling the lights and exhausting, this never mixes with the air in the room, so it doesn't need a filter. Like this:

hmmmm ic.
thanks for the response. so i should at least have a 440 cfm for the scrubber to not get any smells and little fans like squirrel or 4" fans for the lights heat exhaust?

These are all for passive intake(exhaust fan only)

Using the same link, to calculate intake

I'm not going to blow out the math to establish what room intake sizes should be to prevent drag on the system- that get's WAY crazy... Instead, I'm going to propose that we use a rule of thumb stating that “ Intake area should be fan CFM x .5 square inches”

Click to expand...

=390cfm*.5= 226inches square. which is one 16" intake or four 8" intakes.

Some other people like to just use between 1.5 to 3 times the size of the exhaust.

Others like negative pressure in the box, which means using a slightly smaller intake.

hmmmm ic.
thanks for the response. so i should at least have a 440 cfm for the scrubber to not get any smells and little fans like squirrel or 4" fans for the lights heat exhaust?

Click to expand...

Aye, and if your buying a fan with that cfm, it should have a suitable carbon filter to go with it.
I don't know exactly what cfm of a fan to use on the lights, I suppose 10' length by whatever diameter of ducting you use, I'll assume 4" duct, that's only 3.4 cubic feet to clear. I don't think the fans would need to be massive.

Just to clear up another thing, as far as I know, a sealed room has no intake or exhaust, no air comes in or out. So your room wouldn't be a sealed room. So you don't need Co2. There should be 300ppm(parts per million) in the air you take from outside. However, an optimal C02 level (depending on temp) is 1500ppm.
So if you want you can install a c02 system for better and faster growth, you can, but you don't need to.


Just a note on CFM calculation, that specific one is for emptying the room in 5 minutes, for 3 minute air change it's 650cfm but as long as you run the fan for long enough, either should be fine.

Also, the calculation I did has no bends in it, if you have to have bends, the sums need to be done again. But keeping them out is the best thing.

so i was looking at some fans..
would this fan work for the light exhausts?:
http://cgi.ebay.com/NEW-Panasonic-FV-10NLF1-WhisperLine-120-CFM-In-Line-/220746857693?pt=LH_DefaultDomain_0&hash=item336589bcdd#ht_1351wt_1140
or
http://cgi.ebay.com/NEW-Panasonic-FV-20NLF1-WhisperLine-240-CFM-In-Line-/220746861939?pt=LH_DefaultDomain_0&hash=item336589cd73#ht_1357wt_1140

basically a 120cfm or 240cfm for lights?? im gettin 2 for each row of lights btw

and will this work for my carbon scrubber only?
http://cgi.ebay.com/NEW-Panasonic-FV-40NLF1-WhisperLine-440-CFM-In-Line-/220746866587?pt=LH_DefaultDomain_0&hash=item336589df9b#ht_1305wt_1140

a 440cfm..but i dont know if this fan has enough pressure / power.

check them out let me know what you think

Just dropping by I haven't started growing yet but I've read a fuck load of posts on the forum so do with this information as you wish...

Flo Grow made an amazing chart stating what CFM you will need and what temperature will occur in reference to that CFM... Link below
https://www.rollitup.org/grow-room-design-setup/419563-ventilation-chart-calculator.html

IMO: You are probably going to need some hellish CFM to cool four 600watters...

Good luck

p.s. if you draw cool air from outside of the room then you shouldn't have to have carbon filters on them.. (Saves a bit of cash and time)

thanks for tha post.
im kinda slow... its best if you just tell me what cfm fans i need and thats that XD
basically ill be following scaldyballs new design now.
so i need one fan for the carbon scrubber to clean a 10x10x10 sealed room.(straight duct out, no bends) it will be running 24/7
and i need 2 fans, one for 2 600w hps lights to exhaust the heat.. also a straight duct out, no bends.

yea i want to use speed control for reduced noise.
so what do i need plz

godhand said:

thanks for tha post.
im kinda slow... its best if you just tell me what cfm fans i need and thats that XD
basically ill be following scaldyballs new design now.
so i need one fan for the carbon scrubber to clean a 10x10x10 sealed room.(straight duct out, no bends) it will be running 24/7
and i need 2 fans, one for 2 600w hps lights to exhaust the heat.. also a straight duct out, no bends.

yea i want to use speed control for reduced noise.
so what do i need plz

Click to expand...

Hahah not that easy mate! I barely know what I need to get!
What are the average temps in your room?

because think.. you have four 600w broken into two fan loops.
That's great its what I would do..
However with only a 400cfm fan on each loop pulling the air through it would mean a rise of about 8degrees(46F) in each of your rooms.. But even then it doesn't take into account for longer tubing or bends(which you have none)..

I would suggest 1000CFM for each loop, then it would bring it down to about 4degreees(23) Which is much more manageable then all you would have to do is have more exhaust fans to deal with that heat. but fuck what do I know.. I'm a noob too.. plus two 1000CFM fans are pretty expensive..

Any experienced growers want to help out? xD

this is my new design for the room.
their is no turns. their all going to be straight duct with no bends..
look at the image.

so how much cfm would i need for each light and how much for the scrubber?
for a 10x10x10 room sealed
View attachment 1534404

godhand said:

this is my new design for the room.
their is no turns. their all going to be straight duct with no bends..
look at the image.

so how much cfm would i need for each light and how much for the scrubber?
for a 10x10x10 room sealed

Click to expand...

If you use 1000CFM fan on one 600w HPS loop(two 600w) then that's around 500CFM each.
I think the best temp range for MJ is 70-80F (I think the idea is around 76F somebody correct me? and MJ growing stops at 90F I think..)

See attached photo... I'm not sure about the Carbon filter... Maybe a 500CFM will do?
Its really dependent on your outside grow box temps... (The cool air you're drawing in)
you should just do some reading man.. Heaps of information on this forum
https://www.rollitup.org/indoor-growing/90893-ultimate-odour-control-thread.html For cheap ways to make Carb filters

Just realized my carb filter design probably wont work since It'll just take from the carb filter closest to the fan (The path of least resistance) best bet would be to implement it into the middle room and then try and make the vent lengths equal somehow.. You'll also need smaller fans blowing over the plants to help the stems become stronger...
(and helps prevent bud rot when in flowering stage)

Post #6 guy uses a 260cfm to cool 2 inline 1000w hps'
http://www.gardenscure.com/420/lighting/129603-1000w-hps-big-decisions.html

going by that, a 240 on each should work, his circumstance might be a lot different that yours though, or it might be the same. Unless an expert show up to advise ya, you'll need to read up on the different circumstances different people grow in to find one close to yours.

@millsie, I think that chart is for full grow room ventilation, not just the cool hoods. Just venting the cool hoods should require significantly less cfm, I think.

Where are all the experts anyway, I didn't come onto this forum to give advise.

thanks for the post.
i know. i need expert help with experience.
im reading mixed / inaccurate / wrong information. its all so confusing XD

SCALDYBALLS said:

Post #6 guy uses a 260cfm to cool 2 inline 1000w hps'
http://www.gardenscure.com/420/lighting/129603-1000w-hps-big-decisions.html

going by that, a 240 on each should work, his circumstance might be a lot different that yours though, or it might be the same. Unless an expert show up to advise ya, you'll need to read up on the different circumstances different people grow in to find one close to yours.

@millsie, I think that chart is for full grow room ventilation, not just the cool hoods. Just venting the cool hoods should require significantly less cfm, I think.

Click to expand...

Interesting I think you could be on to something there...
Did some background research 1 cubic foot = 1728 cubic inches
My grow box = 56"x44"x24" = 59136"
59136" / 1728" = 34.2CFM required to change all the air in my room in my grow room in a minute.. lol.

I was looking for 1k CFM lol.. wow.

I still might look for something around 200-300CFM just so I can get my bulb/cooltube closer to my plants...

godhand said:

thanks for the post.
i know. i need expert help with experience.
im reading mixed / inaccurate / wrong information. its all so confusing XD

Click to expand...

That's the problem with the internet =[

dont have to run the fans for the cooltubes 24/7, only when the lights is on. IMO

as for Millsie's carbon filler design, shes right on her flaws, but then what do i know im a noob as well XD
IMO i think you just need one carbon filler intake, just not sure where the "intake" should be located at.
im thinking it wouldnt even matter really. put it in a corner outta way. and of course you need a couple
mini fans to help stimulate mother nature.

I wish you luck with your grow.
Z

eh unless you want to try this design,.. unless its not recommended LOL

red box = carbon filter