depending on which part of the country you are in? build a box that is acoustically deadened around your window. that way you can leave the window open about four inches. go to grainger, pick up a six inch blower motor, cheap one is about forty bucks, cfm is 180. use that to supply fresh air into your room. will cool your room no problem. to make it more efficent you can add an exhaust fan as well. just make sure you put something on the exhaust side for odor control.
redneck1 Reviewed by redneck1 on . Heat Hi, I have just finished setting up my grow room, complete with lighting. I began monitoring temperatures last night. The room stays a pretty constant 75 (50% humid.) unlit, but once the light was on a couple of hours, it raised to 80. I don't know what it will be like once its on 18 hours! Any suggestions to lower the heat that I haven't thought of? Background: 10 X 10 X 8 carpeted, top floor spare bedroom. 400W MH light Rating: 5