How Much Ventilation Is Too Much Ventilation?

[HAPPY GRASS]

I have a 6ft high 288 cubic foot setup and I was thinking of buying a 420 cfm exhaust fan with carbon filter from HTG. I'm trying to avoid having to buy intake fans I just want to make two holes in the bottom as an inlet and cover them with this carbon padding I found at my local hydro shop. Any suggestions?

 

[yankee7568]

Each fan has a rating that tells you how many cubic feet of air per minute (CFM) it will move. When dealing with above average temperatures you will want your fan to exchange the grow room air 3-5 times in one minute, so for a room that is 40 cubic feet, a fan that is capable of moving 120-200 cfm (cubic feet per minute) is recommended. If you only want to replace depleted levels of co2 and are growing in a closet using fluorescents, one room change per five minutes (divide room size by 5) will be adequate.

To calculate your room size, multiply Width by Length by Height, this will give you the CFM rating required for one room change per minute.

Air that’s exhausted will be replaced by fresh air, which is drawn from

Passive Intakes-
located opposite the exhaust at the floor of your grow room (Recommended for closet grows) or forced in using another blower (recommended for larger grow rooms).

For internal circulation oscillating fans are In my opinion the most efficient devices for circulating air in a room. The gentle back and forth sway of the fan is very beneficial for the developing plants. These fans tend to keep anaerobic moulds down by constantly freshening any potentially stagnant air. Home improvement centres carry a large array of various types and styles of air-moving fans, there are wall-mounted styles available and most are relatively inexpensive.

NOTE: To convert CFM to CMH use the folowing formula CFM X 0.03 X 60 = CMH

To help maintain a lower room temperature follow this link detailing how to construct a DIY- Air-cooled Reflector

Author: MedMan

hope this helps

 

[Hightide805]

i have a little bit bigger fan that that, and i still am thinking about bringing in air, it just gets too hot still.
are you using a hps?

 

[HAPPY GRASS]

I just bought a 424 CFM fan with Carbon Filter Combo from HTG and I hope it works well, I also have an AC Unit built into the room that will help me with the heating problems. I will be using a 1,000HPS Lamp and maybe a 400 MH for veggie in a built in chamber in that same 288 CF room. I was thinking of using cfls but I just think I am better off using a 400 MH instead because in order to match the Lumens I basically have to use the same wattage.

 

[HAPPY GRASS]

I have a 1,000 Watt HPS with a hooded vent which I will exhaust my 424 CFM carbon filter through and out of my grow room. I am really considering getting some Flows, but I dont want to use a 4ft lamp for one because it doesnt fit, veg room (4ft x 21/2ft) so I was thinking about running 6-10 43 watt bulbs but they only give out 2600 lumens a piece for a total of 15,600-26,000 Lumens which is already 258-430 watts and a 400 watt mh will give me 30,000+ lumens so I am in a little bit of a stand off right now.

 

[HAPPY GRASS]

I found these 2ft, 110w, 2 bulb(55w/bulb), T5 lamps that emmit 10,000 lumens. They seem really good on paper but if they are the real deal I can get 30,000 lumens from 3 which is almost the same as a 400w MH. and they are only $69.95 a piece. Which seems pretty good cause I will be saving almost 100w and the cost for the lamps and bulbs are cheaper. Check it out... High Tech Garden Supply