Window AC in a Dormer

Window AC in a Dormer

I just finished our attic, and while central AC is part of the long-term plan, I need a temporary solution for this summer. The only window in the main room is in a dormer in the middle of room, which basically means its at the end of a short hallway maybe about six feet long. My understanding is that a window AC is vastly more effective, but Im worried that setting it back like that will harm the effectiveness of the unit. Should I consider a free-standing unit instead Or perhaps upgrade to a higher BTU rating Or am I just overthinking it Part of my concern is that if I buy something now, I wont realize theres a problem until summer really gets into gear and its too late to return things. Any advice appreciated. EDIT: Room is 330 sq ft not including the dormer, which is square in the 8K BTU AC according to this Energy Star chart. Aside from the obvious monetary consequences of getting more AC than I need both in purchase price and energy usage, Ive also been reading that too much AC can actually lead to a less comfortable environment so Im really unsure which is the best way to go.

If the window is of the type to accept a window unit single or double hung, up sliding use a window unit in the window. I think the cold air will spill out into the room just fine, but, if necessary, you could get an inexpensive pedestal fan or floor box fan to increase circulation. As far as the BTU rating, how large is the room