Yes correct, but what about the heat? Even with a fan blowing on them its gonna be 90+ degrees.
Not true. Depending on the efficiency of your design, the airflow with intake + exhaust can make a dramatic difference in your room. Intake would be a bit more critical, as that's where the cooler air is (heat rises, cold falls). For my grow box, I have two intake fans on the botton near the floor) and one exhaust on the far upper-right corner. I use 3 120mm computer fans on low voltage (5vlt instead of 12v for noise purposes) and those things constantly dry out my soil quickly (the plants are still seedlings). The less crap you have in the area (cables, wires, ect) the better the air flow in your room. Tempeture drops can range from 5-15 degrees better, depending on your design. I havn't been growing weed long, but I know a shit-load about computers, and computer airflow in case is critical for power users. This knowledge can be applied to any enclosed "space" needing ventilation/temp control. Hope this helps.