There's a pic of my therm. a few post down from the beginning. I have a big portable a/c unit in the room. It hardly kicks on at all this time of year here in Michigan. I have a lot of fan circulation and always have the door opened when lights are on. With it closed and in the summer the a/c kicks on regularly. No exhaust other than the A/C unit. That is a bud room only temp. 78 RH 40's with lights on. At night there's a heater in there that won't let it get below 65 (good purpleing up) and RH goes up to high fifties /60. Only one strain didn't like all that light (old family purps) and I believe that's why the very tops burned a little. With the door closed and lights on without ac running it got to high 80's/90,s. If I didn't catch that a fuse (a/c) had blown when I wasn't home and door closed it could have got up well over 90. You will have to leave the tent door opened with lights on obviously or you'll have heat issues for sure. It sucked having to be home evey day to open the door before I got a/c. If I leave before the lights kick on I have to turn the a/c on with the heater running. No ac (exhaust) at night with the heater on to keep it from running nonstop. I love my 315's. good luck