I have 1300 watts of hps going now and the heat is def no joke. I have 2 AC supply vents that I ducted strait from the main supply plenum and installed right n2 my grow closet and I keep the fan on my A/C set to on so the air is always ciculating even when the asking temp (I keep the T-stat set to 73 F, and yes between the lights and A/C always runnin my power bill is high) is satisfied. I also added another vent in the closet directly above the plants and it hooks to an inline fan that is pulling 640 CFM outta the closet and then runs to the other side of the house and dumps the air back into another vent I added in the guest bedroom closet. Even with 1300 watts going all this allows me to maintain temps at the tops of my canopies at about 77 F. I think thats pretty damn good. It helps being an AC tech. I also use my central AC system to control humidity as well. A lotta people don't know this but you can buy a device called a dehumidistat and wire it n2 ur AC system (central systems only!) and use it to control humidity in ur home. Here is a pic of one of the vents I added in my closet. Looks like it belongs there doesn't it! The part that looks funny is that there are 3 of these in one closet. All of the ductwork as well as the inline fan are in the attic.