has anybody ever ran a small duct off the fan end of a ballast & plumed it in to the exhaust to take that heat outside.& if so would u plum it in before the fan or after to help hold down the heat ya think it would help.
It is in the back of a outside building 10x4x8 like a big closet u would never know its there. 600 watt air cooled with 6 inch vortex fan for exhaust. Pull though light passive intake in the floor.
You just have 2 wires that need to run from inside the box to the ballast outside the box. You could even run the wires through your venting hoses if you do it properly. A shelf on the back of the box that is against a wall? A "storage container" on top of the cabinet? Or, if you have 10 feet of height, a shelf at the top 8 or 10 inches high that separates the grow space? Do be mindful of the heat the ballast generates and the material it sits on. Here's mine - all venting and stuff on top outside the grow spaces. My 2 150 watt ballasts are mounted on the right. Those are my Flora Series nutes in the container on the left And my :watchplant: chair on the right.
It sounds to me like you have a digital ballast if it is like mine it has a long cord. Get creative and hide it. Mine is out side the box, If it over heats your done.
I would have to say 5-10 degrees..........my 400W ballast is outside my grow area, and when its running its hot to the touch so I would imagine atleast 5-10...IMO.
check out the link in my signature, it is a silent exhaust design the eliminates all ballast heat from the grow. My grow room stays MUCH cooler this way.