ducting and cooling help

i have a section 12'x6' that i have separated with panda film to create 4'x6' veg and 8'x6' flower rooms. there are no physical walls just the pando film blocking the rooms from each other and from the rest of my room(master bedroom).
i plan on getting a 600w hps and 400w mh next wedsday. i just purchased a 6in carbon filter that the hydro shop guy said should be be plenty for the size of my rooms. he said he would set this up from the 6in carbon filter to 6in inline fan to 4in ducting(6in to 4in adapter inbwtn) to one of the lights out to the other light and then out the window. he said this will be simplest most efficient way to cool the rooms and remove the odor. question i ask is is he correct? he seems to know his shit and has been helpful thus far, but this part is the most amount of money and dont want to be paying out of unnecessary expenses.

if this is the way to go about addressing these issues, how exactly would i have the duct to my window? is there an adjustable air proof mount that i can buy that will fit both the 4in duct and window?

also since i have no walls in my grow area is it ok for the ducting to go UNDER the panda film then up to the lights? every setup iv seen has the ducting suspended from the ceiling, so im asking is that because the air flow gets restricted going up and down?
any thoughts suggestions ideas or detailed questions would be greatly appreciated. i will take specific pics if needed, +rep always

As far as ducting through the window, that is usually a DIY project involving carpenter skills. It almost sounds like you are going to create negative pressure in the room which may cause the Panda film to fail or cause light leaks. Light leaks are one of the worst things for a flowering room. The important factor is how many CFM the blower fan is. The carbon filter will restrict it some and pushing through both lights and then out could be tricky if the blower is not up for the task. I always put the blower after the lights so that is pulling and not pushing. Just my two pennies.

i see. he did say another option is to have the fan by the window, so that it is pulling instead of pushing..
and the cfm of the fan, 6x12x8= 576, so i will need at least a 1000cfm fan correct?

That is a bit extreme. You may find that to be over kill. 800 should be plenty pulling through a carbon filter and 2 lights.

Just like Tommy said. Negative air pressure not a real good thing as your sucking air into your grow room from all the little nooks and crannies but if your not doing a sealed room (which I doubt you are) then not a big deal.

First question... why are you going down to 4" ducting? Most hood and your CF are 6"....

In terms of the window.. Get yourself a sheet of the pink rigid insulation, a tube of liquid nails and a roll of foil tape. Cut, saw, gouge, glue, and tape yourself a piece to stick in your open window where the duct will exit. Try to make it look legit or not draw attention if it is visible.

I think a much better way to set up a room is to have the inlet to the hoods OUTSIDE the room (from the adjacent space, NOT from outside the house/heated space), flow through your sealed hoods, and then exit. Then just attach a fan to your CF and hang it from the ceiling and "scrub" the air when it gets stinky.

The advantages to this set-up are:
1. Much better airflow through the hoods as no CF resistance
2. NO chance of smell ever leaving through the exhaust as the entire cooling system is sealed and essentially "external" to the grow room.
3. Easier to install and move your lights around later as you don't have to move that heavy ass CF
4. You can put your CF anywhere.
5. You increase the live of your CF as you are only pulling air (and dust and moisture) through it for the last 4 weeks or so of flower.
6. You can purchase a smaller CF when "scrubbing" and have the same effectiveness as a larger one.
7. You can use the aim the exhaust of the CF wherever you want and use it to maintain good airflow in the latter stages of flower...which is very important.
8. No negative pressure in grow room which not only creates a vector for pests to get drawn in and makes it difficult to accurately control temps, plants do not like sitting in a negative pressure environment. ergo..growing in a vacuum.

Disadvantages:
1. You will need to buy an additional fan to mount on the CF.
2. Slightly higher electricity costs for one month. (but it is pretty damn marginal).

matatan said:

i see. he did say another option is to have the fan by the window, so that it is pulling instead of pushing..
and the cfm of the fan, 6x12x8= 576, so i will need at least a 1000cfm fan correct?

Click to expand...

The cheapest fan you can find will work just fine for two hoods as long as you don't completely kluj up the routing of the duct.

legallyflying said:

Just like Tommy said. Negative air pressure not a real good thing as your sucking air into your grow room from all the little nooks and crannies but if your not doing a sealed room (which I doubt you are) then not a big deal.

First question... why are you going down to 4" ducting? Most hood and your CF are 6".... .

Click to expand...

the hydro shop guy told me he was going to "throw in" the upgraded hood, dont know the exact model but its Sun Light Systems. and in that hood, dont know about the original, he said is a 4 inch hole.

legallyflying said:

In terms of the window.. Get yourself a sheet of the pink rigid insulation, a tube of liquid nails and a roll of foil tape. Cut, saw, gouge, glue, and tape yourself a piece to stick in your open window where the duct will exit. Try to make it look legit or not draw attention if it is visible.

I think a much better way to set up a room is to have the inlet to the hoods OUTSIDE the room (from the adjacent space, NOT from outside the house/heated space), flow through your sealed hoods, and then exit. Then just attach a fan to your CF and hang it from the ceiling and "scrub" the air when it gets stinky.

Click to expand...

im sorry but i dont understand what u mean here. i think what ur saying is instead of going out the window have it just exhaust in my room? i dont understand... sorry can u explain from enter to exit the whole way through pls?

plus rep for both u guys btw

instead of having the ducting start at your carbon filter, it simply starts through a hole in the wall of your grow area and sucks air out of the adjacent room. Then it flows through your hoods and to the outside of your house.

No smell will leave the house through this system as no air from your grow room is entering the ducting and hoods. You control smell within your house with a CF and fan that just sits in a corner and runs when it gets stinky.

ok?

legallyflying said:

instead of having the ducting start at your carbon filter, it simply starts through a hole in the wall of your grow area and sucks air out of the adjacent room. Then it flows through your hoods and to the outside of your house.

No smell will leave the house through this system as no air from your grow room is entering the ducting and hoods. You control smell within your house with a CF and fan that just sits in a corner and runs when it gets stinky.

ok?

Click to expand...

That ducting setup sounds vaguely familiar.... see my journal for a pic of what he is describing. You'll have to wade through it and find it (find post #143 and read and look at the pics following closely), go from the end backwards and look at the ducting on the lightwork.

My ducting comes in from two rooms over to my "grow" room from a filtered entrance through the ducting, pulled in with inline fans, through each of my hoods, and exited out through my hoods with the help of another inline fan, exited from my "grow" room up through the walls , up through the roof of the house where its assisted by a third exhaust inline fan.

Clear?

X

matatan said:

i have a section 12'x6' that i have separated with panda film to create 4'x6' veg and 8'x6' flower rooms. there are no physical walls just the pando film blocking the rooms from each other and from the rest of my room(master bedroom).
i plan on getting a 600w hps and 400w mh next wedsday. i just purchased a 6in carbon filter that the hydro shop guy said should be be plenty for the size of my rooms. he said he would set this up from the 6in carbon filter to 6in inline fan to 4in ducting(6in to 4in adapter inbwtn) to one of the lights out to the other light and then out the window. he said this will be simplest most efficient way to cool the rooms and remove the odor. question i ask is is he correct? he seems to know his shit and has been helpful thus far, but this part is the most amount of money and dont want to be paying out of unnecessary expenses.

if this is the way to go about addressing these issues, how exactly would i have the duct to my window? is there an adjustable air proof mount that i can buy that will fit both the 4in duct and window?

also since i have no walls in my grow area is it ok for the ducting to go UNDER the panda film then up to the lights? every setup iv seen has the ducting suspended from the ceiling, so im asking is that because the air flow gets restricted going up and down?
any thoughts suggestions ideas or detailed questions would be greatly appreciated. i will take specific pics if needed, +rep always

Click to expand...

I don't see why the ducting couldn't go under the panda film. Ventilation is the most important, yet the trickiest part about growing. Not only is proper ventilation (AC, ducting, fans) expensive, but it's rather difficult to properly design a good setup. Nothing affects a plant more than extreme temps, so the importance of proper ventilation can not be overlooked.

check out around the 2 minuit mark oh ow to build a window box
http://www.youtube.com/watch?v=M4--jcClnes
i build a light trap in window boxes

Every 90 degree angle you put in your duct reduces flow around 20%.

Plus your likely to step on it and crush it. Don't reinvent the wheel just hang it from the ceiling like your "supposed to"

Light leaks are the problem with using panda film to separate the 2 rooms. Do be mindful of that however you decide to duct the lights and scrub the air.

got some ducting straps and velcro to hang the ducting. one last question, so from where the ducting starts, outside the grow area in adjacent room, that getting pulled into the room is the 'fresh air source' correct? i asumed that it had to come from outside for some reason.. also then is it necessary to exhaust out the window at all? why not exhaust to the same adjacent room in the opposite corner?

just a few tips ive read....

you can put stockings over the ducting to act as a filter for dust and bugs.....so that wont be a problem...

since its in your bedroom im gonna go out on a limb and say you have ac right?..i would run a small cool air intake to help with temps and negitive air pressure..

I would say get an 8 inch inline fan. run it like this...... CF-LIGHT-LIGHT -FAN- , this way you only pull cool air into your CF extending the life of your gear. you can get booster fans for like 30 bucks shipped on ebay that only use 30 watts and will be pumping cool air into your grow room. Should also help with pressure...good luck

also i have seen people trying to save money actually glue the film to cardboard to help with light leaks and add some reinforcement.

as legal flying said... you suck air in from your bedroom thru a duct - light 1 - thru a duct - light 2 - thru a duct - outside
thats your lights cooled

now you need a completly seperate ventilation system for your actually grow room, put the CF inside the flower room, suck air into the CF - thru a duct - fan - thru a duct - outside

both duct exits will be to the same window or whatever, you will seal this with a sheet of ply wood with 2 holes, one for each duct. You can disguise this with curtains or whatever if people can see it from outside.

you then need an air intake for your room, if you can suck it in from outside do it, other wise just suck it from your room.

As far as the panda film divider wall, just cut a hole in it the size of your duct up the top and tape around it

i recommend 6 inch duct for everything, get 2 x 6 inch hoods or cooltubes

ignore the special deal the shop guy offers on a 4 inch hood

I would run your room at a negative pressure so that no smell can escape without going out the CF

I would re-enforce your flimsy panda film wall with a basic wood frame

ventilation is the second most important factor in a grow setup, after lighting

Don't think of fresh air as outside air, think of it as air from another room that hasn't been depleted of CO2.