Vent fan

Last grow I just did CFLs. Good enough. But I bought a 150W HPS for flower. I'm not sure if I'll hook it up though cause it'd take some doing. I have to jerry-rig the whole thing. I'll have to vent the heat through a hole I have to cut through the closet wall. But I'm wondering about the fan to push/pull the hot air through the ducting. Is it better to push the air (fan before ducting) or pull the air (fan after ducting). I ain't gonna cut a hole in the side of the house to duct outside. But I'm wondering about the fan to push/pull the hot air through the ducting. Is it better to push the air (fan before ducting) or pull the air (fan after ducting). I think a 4" fan will do nicely but I'm considering using the computer fan I have exhausting my cabinet now. It's pretty weak though and doesn't do much where it is now.

I think you might be able to tell, I'm ripped.

More often than not, exhaust fans are only hooked up one way. However, it is better to have the fan in the room, pushing air out. That way, all the air the fan is pushing out is leaving the room, and you don't have to have the fan outside, or between two lengths of tubing. But it doesn't really matter that much, unless noise or smell are an issue.

Oh, also, bathroom vent fans work well for small grow rooms.

Pushing is more efficient than pulling. 150W isn't too hard to keep cool and a bathroom exhaust fan works great.

I used to a Sunon 120 mm fan (95 cfm or so) to exaust a cool tubed 150 HPS and that was also the vent for the cab itself. Worked good with decent intake vents.

a 150 shouldnt really get hot enough to have to vent outdoors(mine was less than 6in. at the end of flowering and still wasnt that hot with a fan pointed in the general direction). i know people have different ideas about which is best pushing or pulling your exhaust, ive read pulling is better but it depends on how much vent pipe and how many turns in it you have to have for your setup.