OK so I'm trying to figure out if this setup sounds fine. I have a 2' x 4' x 7' tent with a 400 watt HPS. I am planning on using a 6" inline 400cfm hooked to my hood. The hood would also be the exhaust for the tent itself. There will be no filter as smell is not a concern. There are plenty of passive intake ports. I am wondering if this should keep temps reasonable with only one fan exhausting the light and tent together. Sent from my Z970 using Grasscity Forum mobile app
I exhaust my 1000w with a 4in 172cfm and maintain about 80-82, I don't even put a hood on my 400w. If its super hot where you live then you might have a problem but you'll probably actually want a fan controller to turn you fan down a little bit.
I live in the in the southeast so the summers can get in the high 90's for weeks at a time, but would you say it's OK to exhaust air from the tent through the hood, eliminating the need for two fans? Sent from my Z970 using Grasscity Forum mobile app
I have two 600 watt cool hood lights in a 2x4. 440 cfm fan/filter dialed down on a speed controller right now the lights are on 400 each, 800 total but I can run 600 each. Only the 1 inline fan for both lights and passive intake. Its all about the temp of the intake air. You can have the biggest inline fan you can find but if its pulling warm air its not going to help much. Sent from my XT1028 using Grasscity Forum mobile app
Duct that exhaust air away from your grow. Mine goes outside in the summer and helps heat the house in the winter. My grow is actually in a gardening shed on the back of my house. So venting in my house is still venting it out of my grow Sent from my XT1028 using Grasscity Forum mobile app
4' is a reach for 400 hps and not a big heat factor in that size tent. 600 to 800 watts should be best fit.
Well I have a/c in the room the tent is in so I believe I can keep incoming air at a low enough temperature. I just want to make sure 440cfm isn't going to be too much for one 400watt in a 2 x 4 Sent from my Z970 using Grasscity Forum mobile app
No it won't be too much. I wouldn't put a smaller fan in my tent. You said your buying a speed controller correct? They're cheap and give you great control. The minimum I would have in my tent is around 200cfm regardless of the light source because i like turning my air over 5x a minute. You'll here people recommend atleast 3x. They do more then just remove heat. They also keep a fresh steady supply of co2 on hand. I scrog and do 5x just to make sure its not getting stale when my canopy gets packed. 200-250cfm is approximately what I had my speed controller set at. The extra cfm does 2 things. It gives you a bit more power if something ever happens and you need to turn it up a bit. In spring and fall I can avoid running my a/c just by turning the fan up. 2nd a larger fan turned down is usually much much quiter then a small fan on full blast. Even though they would be running roughly the same cfm. You know about passive intake and negative pressure? How your tent will be slightly sucked in? This makes sure there's adequate air exchange and if smell is a concern in keeps smells from being pushed out instead if going through the filter. I promise man you can run that fan full blast with all the bottom passive intake vents open and it will be fine. Sucked in some like it should be. There will come a time you'll be glad you have the extra power and with a speed controller you're golden Sent from my XT1028 using Grasscity Forum mobile app
I thought yours was 6' tall. Ya man at 7 foot with that extra space you're good man. You'll be glad you didn't go smaller. It can be done but its nice to be ready. Sent from my XT1028 using Grasscity Forum mobile app
Thanks a lot I think I'm gonna go with the 400cfm and the speed controller. I would rather be safe than sorry. Sent from my Z970 using Grasscity Forum mobile app