If the room is insulated and sealed properly you should be fine with 4 tons of ac per room. I have two rooms 9 epaps each with co2 burners 14'x17'x10'. In one room I run the Excel 4 ton Elite series with the built in d-huey works just fine and its been in the high 80's low 90's here. in the other room I have an excel 4 ton xl series with a quest dual 155 for a d-huey also works just fine. Both rooms cycle just fine. I do all this with 200 amps. I also have another 6k in veg and lots of other fans and power consumers.