My grow room gets too hot in the summer

i usually open up the rafters in the attic and add a fan to blow on the plants and light, will the ecessive heat cause a fire ????????????????

no just keep the fan blowin and put a fire alarm in carse anyway,

Fresh air, air circulation and if that dont work you are going to have to invest in a portable a/c unit

I had same problem, I added a A/C unit that has a digital temp gage to the room and then I added a 12" attic fan with its own temp gage and a vent in the wall. This helps me to cool the air around the room which combined with the A/C it works awsome! My temp is right on even on the hottest days!