heat control question

[smizl PLZLs]

I have 2 150 watt hps' in a 3'x20"x5' tent. I ordered 2 - 240cfm inline fans, and was wondering the best way to use them. 2 outtakes? 1 outtake, 1 intake?

 

[calicat]

In my room I use them as 1 intake and 1 exhaust. Its a good idea to have negative pressure and the ratio is 1:4 (intake to exhaust).

 

[Clonex]

I would use one to cool both lights and one as an exhaust.
Unless your area is sealed , negative pressure will draw in enough fresh air.
(only applies to your smaller light set up)

 

[ASMALLVOICE]

In my room I use them as 1 intake and 1 exhaust. Its a good idea to have negative pressure and the ratio is 1:4 (intake to exhaust).

looks like a bit to negative. Stick with a 2-3 to 1 ration intake to exhaust. If you have a 6" fan doing 200-300cfm you will need a min of 12" to 18" of intake opening ( can be several holes to total that) to accomodate the "pull" of the fan.
Any less and you will strain the equipment unnecessarily and possibly shorten its life span, a fan will be quick to tell you if it is starving for makeup air.

Peace

Asmallvoice