The room they die in...

What you see:
1000w Air Cooled P.L.
747Cf/m closed circuit inline fan cooling light
5,000 btu (unnecessary) A/C
150 cf/m carbon filter matched to a 270 cf/m inline fan
2 fans for circulating air within

What you don't:
42" x 40" x 6'8 (apx. 75 sq ft.) Airtight, I mean AIRTIGHT.
CO2 injection (by timer, no ppm meter)
Walls completely lined with Mylar


The initial problem was that the 747 fan that is cools the light was plugged in, running on full blast. Temperatures remained in the low to mid 60's, actually only a degree lower than what it drops down to at night. In essence I hooked a dimmer switch to this fan and have it running at about 40%, which keeps me at 78.4 degrees throughout, every time. Humidity varies by when they get watered usually around 40-45%. That is the highest or lowest she goes once she warms up no matter how long she runs. CO2 is slowly increased after introduction. Starting at a liberal 1500ppm, (again on a timer, apx. every hour) To a liberal 2200 ppm by week 4 of flowering. While she has not run in the summer yet, I do not believe the air conditioner is going to be necessary at all, so it currently only remains for sake of filling the big empty hole.

There is only one problem that really gets me; Patience.

See any other room for improvement? Let me know. Thanks.

SP

Nice looking setup. Do yourself a favor and periodically check how hot the dimmer switch gets, it could very easily be overloaded by the fan.

nice setup but what do you about getting new air in? or does the ac take care of that?

Thank you Sam I will definitely keep an eye on that.
I inject CO2 hourly. Other than when I open the door in the morning or am otherwise in there poking around the air usually remains inside the room. It is easiest to control all aspects of my room by not bringing in entirely fresh air, all O2 and CO2 levels are maintained temperature and humidity is a constant. As of right now the A/C is just filling the hole in the wall, with just the fan cooling the light alone, It makes temps fall too low, I rely on the light for some heat to warm the plants and therefore maximize thier use of CO2.
Any other tips?
SP

Great setup! Only thing I can see is that your fan is rated much higher than the carbon filter, the filter should be rated to flow slightly more than the fan which pulls air through it.
The way you have it the air will be pulled over the activated carbon too quickly for it to be filtered properly, and you'll lose out on some of the odour control.
That's not to say it wont work, but you may well be able to smell them outside the room, especially late into flower. It depends on how big a factor the smell is to you. Is there a chance that an outsider could pass by your exhaust vent? If so it's not something I'd like to take chances with.
It's not like you have a problem with temps, I'd turn the exhaust fan down to about 40% personally, as long as it's still cycling the air about once a minute there shouldn't be a problem.

Sucking air through a filter causes a fan to slow down and not move the same amount of air if were allowed to suck and blow unrestricted. By adding the carbon filter I effectively cut the cf/m moved by the fan by almost half, making it the correct fan. That and the fan and filter is designed and manufactured to be matched together by the can fan company (Highly Recommended). But if you do purchase a non-matched system, make sure that the filter cf/m rating matches what the fan will actually pull through the filter, not the cf/m the fan blows uninhibited.
Keep 'em comin', if noone can poke any holes in this system I might have to put a patent on it! -Haha

SP

Oh yeah sorry I missed the bit about it being an inline fan, those things do get real shitty as soon as they have to deal with any sort of static pressure (carbon filters, long runs of ducting, bends in the ductwork) but you've obviously accounted for all that.
Great job! How many/what strain you growing?

Another small thing, how are you regulating the amount of co2 without a ppm meter? Sure, you can calculate the amount to release to bring it up to your desired ppm, but how do you know how much your plants are using in between the times it's being injected?
I wouldn't wanna go giving them an OD on the stuff!

All I can really do is calculate at this point. I try to inject less, more often, rather than a lot at long intervals. I think its most likely that I am probably just wasting some. I know that a plant needs O2 for the krebs cycle and it also absorbs some O2 through the roots, but beyond that, to my knowledge the only other gas that a plant uses is CO2. No plants should die from carbon dioxide poisoning, at least at the levels I provide.

SP

P.S.
Originally Posted by ceestyle
Don't be a martyr wasting $100 or more on CFLs to prove they're inferior for flowering pot. <-- I wish more people would take that to heart