Air flow dynamics question…

[jaguarrh]

Hello everyone, long time browser first time poster…

I recently gave up on a cab grow, due to the ambient temperatures here in Australia and decided to size things up a touch to see if temperature control would be a little more manageable.

I have built the framework of a new grow space in my garage and was hoping to get some input on air flow from all the experienced growers out in ic land.

Please understand that I have read lots of the posts here regarding ventilation and have gleaned a lot of useful info from them, but I still find myself moderately confused. I think the problem is I have too many options…

I am familiar with the formula that was on the OG pages and is quoted here on IC to calculate the size of fan I need to use (Q=VxPxCxdT) and am confident I can work out what size of fan I need, once I have settled on a “circuit” or flow path of air in my space. Working out this circuit will allow me to calculate what lengths of ducting I will require and how much this ducting will reduce the effectiveness of the fan I choose.
(sorry about the long winded post)

With this in mind I have attached a diagram of my new rooms and would be interested in people’s thoughts on the best way to use a single carbon filter and fan to ventilate my two rooms.

I intend to place the carbon filter in the flower room (obviously) but would like to change the air in both rooms with the one fan (less expense)

Can someone help me with a circuit diagram ,if you like, of the air flow in my rooms please?

 

[Guest]

I don't know about anyone else but, I kinda had a bit of trouble enlarging your diagrams enough to read things clearly.......maybe that's just my computer (a bit old now).
Anyway, if you're in a hot climate, you might need an A/C unit of some kind to control your temps., no matter how you configure your air flow. If it gets to be 90 deg. F in your garage, it'll never be any cooler in your grow. (I'm sure you know this). My garage gets damn hot during warm weather. I'd think about including at least a portable A/C unit in your plan & know that you'll probably have to vent it to the outside of the building.

Best of luck on your project!!

Bh

 

[jaguarrh]

thanks bh, but as it is coming into the colder months here now i was hoping to get away without the expense of a/c, at least for 6 months.

the temps in the garage are at about 60f - 80f now so about a perfect range really. i just need to know the best ventilation methods.

i know that low level intakes and high level exhaust are the best and that the passive intakes should be larger than the exhaust etc but how do i do both rooms?

i did find this...

http://www.growell.co.uk/ds/instructions/Datasheets.html

check out the 'filter in a box' data sheet.

what do you think?

 

[blazeoneup]

Ok well seeing you are running 600w flower room 8'x4'6" with a 250veg room with some possible cfl's which is 8'x5'x6" i dont see any reason for troubles.

They are split room it appears you have built frames and just lined with panda poly for the walls.What i would recommend i would,If going cheap route use dayton 465cfm blower,I would pull from vent in flower room blow through 600w to the 250w and directly out of the veg room.This will keep the 600 and 250 cool,Now if not going cheap i would get a 8" vortex for the job.

Then cooling the rooms and pulling enough fresh air for each should be failry simple hook up a 465 in both the veg and flower room to the exhaust to outside and make sure you passive intake holes are large enough to pull enough air in.The scrubber i would put on the exhaust of the flower room,This is not exactly a well thought out answer just quick way to do it,I am limited on time i will come back to this thread make a diagram for you and post up.

What you are trying to cool is very simple 850w is nothing to cool,Anyways catch you soon

 

[jaguarrh]

thanks blaze, i look forward to your sketch

ps what do you think of the link to the filter in a box?

 

[jaguarrh]

anyone else got any suggestions, i am getting conflicting information from my two local grow shops.

the only thing that is similar about the ideas from the two grow shops is it will co$t.... quite a lot.

if anyone could help with a sketch of air flow using a minimal number of fans, it would be a great help.

thanks

 

[HYDnout]

I like your diagrams! The parallel flow solution proposed by Growell makes sense, but I think a series flow solution will work almost as well - intake from and exhaust to the outside, intake in the first box, exhaust in the second box, a big hole in the partition between the two boxes, no damper. The second box will run a little hotter than the first. Whatever you decide, I think you should expect some trial and error.

 

[420ponics]

I fixed my heat problems, but I have one room. Here is what I did. built a frame to hold my 55 pound carbon scrubber directly below the cieling (where the majority of the heat builds up) I exhaust it to the attic and then out of the house. Here are some pics...





















Notice the type of ducting that I used. I would simply get enough ducting to run from your veg room to your flower room where your scrubber should be located. Run one vent pipe from the cieling to the scrubber and run the other from the veg room to the ducting above the scrubber (you will have to cut a hole in the ducting above the scrubber). Because you are using one vent pipe with an additional room, I would go with at least a 465 cfm fan if not larger. Try to minimize the length of the ducting as the longer it is, the more "pull" you lose at least that is what I read somewhere on here. Anyway This is only and ONLY if the flowers you are growing in veg do NOT smell enough to be noticed as the air pulled from your veg room will not be filtered. I hope this makes sense. I also hope it helped.

Oh, yeah, as far as the intake being twice as large as the exhaust. I don't abide by those rules and everything is just fine on my side. I don't even have an intake. There is a slight vacuum in the room when I close the closet door (which I can now do with no heat issues ever since I added my scrubber exahausting to the outside). However if I place my hand underneath the door I can feel alot of air being sucked into the room through the cracks etc...so there is air being pulled into the room, but that is only because of the result of the vacuum.

Another option which you may have. Go to your local hardware store and purchase a cheap door ($25). Cut a hole in the door and fill that hole with a box fan. Build a light proof frame around the fan if lights will normally be in the room (this is hard to explain I hope you can figure it out, basically just use some black plastic sheeting and some cardboard or wood) that can be your intake. This may be hard to understand without pics =/ I hope it at least makes some sense. PM me with any questions and I'll be glad to help.

Ponics.

 

[jaguarrh]

hey ponics,

great response mate, thanks for that.

sorry it has taken a while to reply, but i've been away for the weekend, the wifes birthday.... ;p

your suggestion about the branch off to the other room from the duct between the filter and fan is the solution i've been waiting for, thanks for breaking my mental block on this... i will post some pics when i have built it and you can look over your idea...

thanks again.