I did quite a few cycles in various size grow tents and I have encountered and solved many heat and ventilation issues during that time. I wanted to use this thread as a place where people who have grow tent specific ventilation questions can ask here. Ask away!
OK, thanks man. I have a ventilation question. I'm preparing a closet for my very first grow of any kind. The closet size is 3.5 x 3.5 x 8 = 98 cubic feet. I will be using a 600-watt HPS bulb inside a DayStar air-cooled hood with 6" flanges. And I will need to filter the ventilated air. I have 2 Elicent inline fans. A 6" 309 CFM fan, and an 8" 636 CFM fan. I also have 2 motor controllers to dim the fans as needed. I have plenty of filtered passive intake. Should I use the 300 CFM fan to cool the light, AND the 636 CFM fan to vent/filter the room air? Or could I successfully use just the 636 CFM fan for both purposes? Thank You Very Much, Kolchak420
OK, thanks man. I have a ventilation question. I'm preparing a closet for my very first grow of any kind. The closet size is 3.5 x 3.5 x 8 = 98 cubic feet. I will be using a 600-watt HPS bulb inside a DayStar air-cooled hood with 6" flanges. And I will need to filter the ventilated air. I have 2 Elicent inline fans. A 6" 309 CFM fan, and an 8" 636 CFM fan. I also have 2 motor controllers to dim the fans as needed. I have plenty of filtered passive intake. Should I use the 300 CFM fan to cool the light, AND the 636 CFM fan to vent/filter the room air? Or could I successfully use just the 636 CFM fan for both purposes? Thank You Very Much, Kolchak420 ============================= Hi Kolchak, I believe you could successfully control the temperatures using only the 636 cfm fan. The problem is that once you're in flowering the temps can sometimes be under control so your exhaust fan doesnt come on meaning there could be long periods of time between air scrubbings. If you still want to use only one fan I would not use a thermostat controller with it but instead put it on a timer. I would set the timer to run for 10 minutes every 30 minutes. Carbon filter in the closet running to 6" ducting to the air cooled light then out of the closet to a 6 to 8" reducer then to the 8" fan. (that make sense?) If you want to utilize both fans you're going to need 2 filters.
Thank you for the reply. I've been trying to make a decision on this issue for a while now. In my particular case, the carbon filter and all fans used must go INSIDE the grow closet. So, with the light hood, carbon filter, and two inline fans, things could get pretty crowded. But I sure do like the idea of a dedicated fan for light cooling. That way I can put it on a timer to come on when the light comes on, and to turn off one hour after the light goes off. Then my other fan is free to ventilate/scrub air 24 hours per day.
hmmmm, he didn't mention anything about his exhaust being on a timer. Why would you suggest the fans be on a timer? If he is running his exhaust through a carbon filter, then he wants that on 24/7, especially during flowering. Whenever my fan turns off during flowering my room immediately fills up with odor. Run your lights on a timer. Run your exhaust and odor solution, 24/7, no need for a timer there.
My grow area is not a tent, but a wooden box without a top. If you can help me, please do or try. If not, I understand. My problem is, I'm having a hard time connecting everything to where. Is it acceptable to have a carbon filter pulling air through a duct which leads to a hood, which leads to a duct, which ends with a fan being blown out? Or are there too many twists and turns there? Or should I just not connect the hood and have the carbon filter pulling through a duct and out the fan? Also, without having a top on box, will 1 carbon cleanse the entire room of odors? If not, should I buy an Ozone or another carbon filter + fan? Thanks for advice.
OK Bro, I got a question for ya. I have a 4x4x8 grow tent with a 6'' XtraSun air coolable reflector and a Active Air 6'' Inline Fan-400 CFM. I have my reflector runnin with one flange with ducting, one flange open and my inline fan pullin air from the ducted side thru the opened flange/duct port. My tent mem temperatures Fluctuate between 68-82 degrees with most of the time the tent being between 72-78 degrees. I have my inline fan on the 18/6 timer with my lamp, Is this overworking my fan? Should i put it on a thermostat or another timer? (I have both a thermostat and an extra timer) Or should I just leave it AS IS?
Hello, nice thread! OP, help me out please with determining the right size fan for my vent. system. My first grow is going to be in a 20"x36"x60" tent thats inside a closet. (The closet is the type with two doors that slide either way, allowing me to potentialy leave one door all the way open during my grow. Fortunately the way the room in which the closet is eliminates the passerby from getting a peek inside my closet.) So, I plan on having a carbon filter inside the tent and then routed through my 400w cooltube and then out the tent and into the same closet or going through the closets wall and into a hallway closet. some questions I have are: -I feel confident with that. Do you see any issues? -What size/type fan should I get? -Where should I place the fan in reference to the carbon filter, tent/closet and cooltube? Is there a formula or general reference when deciding on a fan for your tent? I was told that you want the air in the tent to be replaced every 5 minutes? (Is this true or should it be faster?) Wont the carbon filter slow the airflow down and strain the smaller fans? thanks for helping in advance.
Absolutely thats ok. Thats how my setup is. If you take a look at the current grow link in my sig, you will see a pic of my tent. Chain starts at the CF, ducting to my cool tube, thru the cooltube, more ducting leading up to the exhaust fan which is pulling the air thru the whole chain. Works perfectly for small grow areas.
hello If i were to exhaust my hot air back into my room from the grow tent, and always keep a window open n that room, would that cause any problems? i dont want to exhaust outsde because the hot air will turn into steam, making it visible.
I do it as well. I only exhaust out of my tent into the room. I know when the window is open it is drawing fresh air because there is an immediate temperature drop in the tent, and the window is all the way across the room. I actually have 2 windows in the room so I can get a nice flow happening. As long as you have good negative pressure going in your grow space, then you will pull that fresh air in. But thats they key. So yea, although not the optimum setup, you can pull it off, and still have very successful grows.
Seriously? How bout some details? Size of the closet? What is your grow setup like? Where is the closet located? Do you have access to drilling holes in the closet? Does the closet lead up to an attic, or out to a a source of fresh air? details and pics would be very helpful to give you solid advice.
30x47x70 is my grow space, and I cant drill holes in the walls. I only want to have 2 plants max but atm just have 1. Only air flow I get in there is when I open the door to check on the plant and have a fan inside of the closet.
having major heating issues the 4 inch fan on the left exhausts the air from the tent out into the room the tent is in and the 6 inch fan on the right side pulls air from the room the tents in through the light and is exhausted outside through the window. light is 600w. im looking for input on a more efficient way to hook this up as my temps inside the tent run around 87-89 with the room temperature at about 75. i have carbon scrubbers for both the 6 inch and 4 inch fans.
Get rid of the intake fan. You have destroyed your negative pressure, so you are not getting any real air flow through there, just air movement. If you have a fan exhausting, all you need is a intake flap open, the fan will take care of the air flow, and will lower your temps. I would hook everything up to your exhaust fan, your filter (if u have one), your light, and have the exhaust fan as the last thing in your chain, and no intake fan. You WANT negative pressure in your tent, and you will not get it with both intake and exhaust fans.
no intake let me try n word it better the 6 inch fan only goes through the light its hooked up to a cooltube and the other end of the tube is ducted to the outside of the tent so it gets clean air from outside the tent pulls through the light and exhausts outside through the window and the 4 inch fan pulls air from inside the tent and exhausts it into the room the tent is in. i have 3 passive intakes on the bottom of the tent
Oh I see. What is the temp of the room the tent is in, and does the room itself have fresh air coming into it (windows, ac) ? I would still compact your chain to one exhaust. If you check out either the 2nd or 3rd link in my sig, u can see my setup (1st grow was different and much warmer). I have a Carbon filter start my chain, with ducting from the filter to the cooltube, then ducting from the cooltube up to the exhaust fan. This way, the heat from the light (as much as possible) stays in the exhaust chain and exits the tent. I keep the room my tent is in between 67 69 degrees (windows in the cool weather, AC in the heat). This allows my tent with exhaust setup to maintain 73 - 78 degree temps. My tent is a DR80, not exactly sure how big yours is. But thats what I would try if you are looking to get lower temps. Either that, or find a way to exhaust out of the room entirely. I can not do that in my present situation, but wish that I could. Good Luck. Peace.