I want to do closed venting on a 1,000 watt hps. The light has 8 inch vents, so I know I need an 8 inch in-line fan. I will only need to vent to light's heat about 15 feet. Does anyone know what size/rating I should buy?
W a 1k, you can easily get away w a 6", maybe even 4-5", depending on a lot of variables... the actual ambient temp vs the temps of air from your draw area, what else you got running in the room, how you run the lines (bend/corners = significant reduction in air flow), & where you place the fan (pulling or pushing). A lot of small things that make a final impact to your temps...
I would go w a 8" which will allow for you have all the issues above covered. It will likely also allow for you to add a second light. Would get a Speedster controller to dial it down, should that be necessary. W fans... always better to go bigger & adjust down vs having something too small for the job. Peace.
thanks GroHi - I'm growing in a sealed room. Have a/c (set at 90), room fan, co2 (1500ppm) & my 1,000 watt hps. It's 100% organic,soil grown. I'm wanting to vent the light (closed venting) only. It's a straight shot - 15 feet. My light has 8 inch vents, but I don't want to get a fan that's too powerful/expensive. I could get an adaptable flange or something if I went with a smaller fan, right? Or, should I still go with the 8 inch fan with a Speedster controller?