Flower room getting way too hot, need some inline fan help.

Hi Everyone, havnt been on here in a while, but I got my grow going quite nicely. I am trying to run 5 1000w HPS in an approx. 250 sq ft room in my basement, 4 of those being air cooled and exhausted to a "hot room". When temperature is too much of an issue to run 5, like now, I have one light set up on a mover to be able to cover the lost space. Currently running a 13,000 BTU portable A/C and another 5,000 BTU window unit 12 hrs/day to try to keep the room cool, but its just not working. Temps are in the mid-upper 80's. I have my lights timed to come on at night, when outside temps are usually in the 50's, but that still doesnt do the trick.

My new plan is to try exhausting the air from the flower room into the "hot room" with a 1500 CFM attic fan, and exhausting the air from the "hot room" outside with an 8" duct booster fan, while simultaneously having incoming cool air from outside coming into the garden with a 6-8 inch inline fan with ducting run to the garden.

I guess my question is: Will a 6" 440 CFM inline fan be strong enough to push air through approx. 15-18 ft of ducting, or should I go with the 8" 720 CFM?


Any help would be greatly appreciated. Thank you in advance.

Go with the larger fan, the 6 inch will not even be close to enough. You can always get a fan speed controller as well to turn things down as well.

Add Co2. Those temps are great for Co2 use.

yea with your set up Co2 would be a minor detail .. that a buy a field

Thanks for the responses guys. I originally had my bloom room set up with only 3 1000w HPS, and temperature wasnt much of a problem with only the 5,000 btu window unit running. I had the CO2 filling the room the first 15 minutes of every hour, and an 8" duct booster fan exhausting hot air out of of the room for the last 15 minutes of every hour...trying to let the plants "bathe" in it for the first 45 minutes of every hour.

....However, now that I've added a couple more lights the heat is just ridiculous. When all lights are on, 4 of the 5 being air cooled, both ACs on full blast, and an exhaust fan running, temps are still approaching 90 F. Ideally I'd like to get it down to 80 or < & be able to hook my CO2 back up w/o it all being wasted.

get a minisplit ac. on your portable, wrap the exhaust hose with insulation and it will help a lot. do not add co2 unless you have the room and plants dialed in, do not add it to fix a problem.

Well, I tested my plan with the big attic fan and that was an epic fail. I got it, installed it and got it working properly, & had an 8" duct booster fan pulling the hot air out of the basement...but it did the exact opposite of what it was supposed to. The temperature rose a couple degrees...didnt drop a single point.

So, on to plan D, E, F, whatever it is I'm on now.

The new plan is to get 2 of the 8" inline fans. Here's a link... http://www.amazon.com/inch-inline-high-efficiency-blower/dp/B004YXDR22/ref=sr_1_5?ie=UTF8&qid=1341864683&sr=8-5&keywords=8+inch+inline+fan

...and have one of these pulling all of the hot air out of the basement, and another one bringing in cool air from outside. Maybe that'll do the trick.

Is the fan for the lights pulling air from outside or inside the room?

Seems to me, portable AC units take a while to start cooling a room down. When you pull air from inside through the lights and out, it's pulling your cold air out also.
If you were to pull air from outside, through the lights, and back outside (or into your "hot room"), I think the AC units would do a better job cooling the room.

MrZogs said:

Is the fan for the lights pulling air from outside or inside the room?

Seems to me, portable AC units take a while to start cooling a room down. When you pull air from inside through the lights and out, it's pulling your cold air out also.
If you were to pull air from outside, through the lights, and back outside (or into your "hot room"), I think the AC units would do a better job cooling the room.

Click to expand...

^^^^^

Thanks Mr. Zogs! I completely agree!

The fans for the lights are pulling air from inside the room.

I do think a completely sealed environment would improve my situation much more. I am going to give this a shot and run some more ducting before spending the money on inline fans. 18,000btu, according to my calculations, should be plenty of AC to cool 4-5 lights, I just need to be a little more efficient with it. +Rep for the great info. Thank you sir.

Zogs nailed it I think. That's the way to go, I would think.
Let us know how it works out

I do believe it'll work. I'm about to make a run to Home Depot for ducting and go get some work done. Will check back later.

Ran some more ducting and finished sealing in the bloom room last night. Also situated the stand-alone AC where its exhaust is now pumped straight outside. Temps cooled down last night to 78.5....FANTASTIC!! I'm going to cut another light on today and see if temps stay ok, and if so, we're in good shape. I'll try and post a pic or two of the setup later.

Thank you again Mr. Zogs, ya nailed it!

im glad it all worked our for ya man still here u starting a new journal? how did that sweet island skunk turn out?

SFguy said:

im glad it all worked our for ya man still here u starting a new journal? how did that sweet island skunk turn out?

Click to expand...

SF guy, How's it goin' my man?

The S.I.S. turned out great...almost 4oz off of it.

mmmmm sweet.! i hit some temp issues too in this run been contemplating chahnging shit around to woprk more efficiently

i think its simply re routing ducting and changing a couple things i should be sittin pretty-er

Ya grow's looking good man. Do you have an AC?

ya just a small5k btu window unit. i was actually looking at a portable stand alone tonight when i get off work its an 8k so id be around 13k btu

Nice. How many lights are you running now? Still got 'em on the movers? I invested in 3 myself lol...they come in handy.

i still have the same setup i was running. but i also have a 400 to veg with now but had to shut that down and move it to my buddies cause its just waaay tooo hot. hit mid 90's and the girls told me me FUCK YOU PRICK!