HELP!! Ventilation

Hi

This is my first grow, i am using a 600w HPS light in a wardrobe and not entirely shure what ventilation i should be using. Would a ordinary 4" or 6" extractor fan be sufficiant

Any help will be greatly appreciated

Cheers

Use two fans. One down low, pointed inward. One up high, pointed outward. See how this works at venting and exhausting. Remember, if the inside temperature reaches 95 deg f for very long, your plants will die.

You need to air cool that light separete from the rest of you ventilation. Go read a few journals. You will find everyone that can't leave the closet door open has discovered this and had to add it. Who the heck was it posted an excellent example of how to accomplish this. This is the one of the reasons I recommend the T-5's for closet grows. Don't produce the heat you don't have to deal with it. Gives you about 2 more feet of usable height for growing and will perform as well as a 600watt hid. Rollitup posted setups showing ventilation.
Assuming you insist on an hid, no a 4" or 6" extractor fan will not do it by itself. Between 2 and four will plus an oscillating fan. VV

ehat size fans would be the best to use that are not expensive as i am on a bit of a budget

get a squirrel cage or inline fan. calculate the cubic feet of your box. you will want a fan that will change that amount in less than a minute with a 600 in there. C.F.=C.F.M. so u can change the air every minute. u will want alot of good ventilation in that box. if not your going to run into more problems than ya got now.

venting the light separately from the room will make your plant's life much happier.
I agree with billybob88 but would recommend your fan can change the air 3 times a minute (3x3x6=48 cubic feet so a 150 CFM fan would be ideal for that size room).

Get a vented reflector with glass for your light and vent that with a smaller fan and you shouldn't have a heat or burnt leaf problem.

what does cfm mean

cubic feet per minute. Good advice email, venting your lights makes your life so much easier. i can touch the glass right beneath the bulb and not burn my hand with my vented lights

thank you man

oh fo sho!

waht am i chopped liver?? lol VV

the light is an open light with reflector how would i vent this seperatly

you'd have to enclose it yourself or purchase a reflector that comes with duct attachments and glass cover.

would a fan with a carbon filter still take away the heat

well not just one golden option is ganna solve heat issues. you will need to vent your light and still vent the room with fresh air. i assume u could get a powerful enough fan to use the open end of the light as your exhaust and then duct the light out of the room and put a carbon filter on it. i say at least a 270cfm inline fan. i would go with at least 350cfm to be safe.

After mutch thought and sound advice from you guys, im still considering using PC case fans. I figure i have room on the shelf to fit around 20, which wouldn't cost me anything because i have a friend that works with computers

Does anyone know if this would extract the heat or the noise this would create?

i don't know if PC fans alone would do the trick. If you knew the CFM rating of them you could figure it out though. I saw you mention a carbon filter - they won't do anything for heat - they are for reducing smell.

Would a couple of these do the trick
Find SUPER DUPER 100mm in line extractor fan hydroponics on eBay within Hydroponics, Plants Seeds Bulbs, Garden Plants, Home Garden (end time 04-Nov-07 08:27:58 GMT)

Let's see how my math skills hold up....
107 CMH (Cubic meters per hour) = 350 cubic feet per hour = about 6 CFM.

That ain't very much. You want to exhaust the entire room (ideally) about 3 times a minute. So if your room is 3ft. x 3ft. x 3ft. (that's 27 cubic feet) you'd need like 15 of these things to vent the room three times a minute.

You may want to check my math but these look as though they wouldn't even cool off HIDs. You should consider an inline vortex fan (or equivalent) for exhaust.

Actually its more like this.
Room Air--->light--->fan--->filter--->outside

This way you pull the old, stale, STINKY air out of the room over the light and it cools the light, then it goes through the fan (duh ), then it goes through filter to get rid of smell, then it goes outside. This is how mine is set up, it works perfect. See the duct runs out of the room just makes a uturn and comes right back in. It is towards the top obviously. There is a 6in hole at the bottom of the room so it also pulls in cool, fresh air as it removes old air at the top. Then all this air goes through filter which is attached to the side of the shed. You could keep it inside or hide it somewhere else if you wanted to. There you have it. The air coming out is clean. The air inside is fresh. See in the top left of the first pic. The duct runs outside, makes a u and comes in right beside itself. The second one is just another view of that. The third pic shows the fan sucking all of this air across the light. The left side of the fan is the big hole, the right side is the small hole. It sucks from the right to left. Not sure of exact cfm, ill find out today. This is a active exhaust, passive intake. There is a 6in hole on the bottom right side. This is where it sucks in nice cool, fresh outside air. Covered with a filter And the third pic is the filter on the outside of the building. Buy doing this not only am i clearing all the air every so often, the air in the rooms is changed constantly. This fan is sucking in fresh air non stop and pulling out the hot, stale, stinky air non stop. Works like a charm! What doyou guys think of this?