Oh this will be fun. I am gonna guess, solely based on information obtained through months of research that he does not have adequate ventilation and his grow box or enviroment is to small. A large area would not create a serious amount of heat unless it was in a 90 degree room to begin with. Most houses run 70-75 on average. If he has a tent with a high powered lamp which I doubt he does with growbox in the title, then were talking a whole other scenario. I'm going with not enough ventilation of air let alone fresh air and grow box to small