For the OP. I think what your saying is you want to put the rad into a cooled am of air from an AC window unit? It's been done and is viable. Make sure you have air over the rad as normal with fans, and only turn the AC unit on till the PC has been on a bit, you shouldn't have any problems unless your humidity runs over 85% or so. Check your hoses and fittings for condensation tho once you get it up n running.
You can get some awesome temps for overclocking with a bit of care. I'd hate to run a window AC unit 24/7 on high, the room temp could get cold and the electric bill......
I live in Vegas, it got to 100F today, not even warm yet. My house stays at 79-81 for the whole house AC. My PC room with a fan blowing hall air into it 24/7 still got to 89F with a 3 hour load test on the CPU/GPU (rig in sig). I'd love to toss a window AC unit for just my room, but the noise from the thing and a $80 increase in my elec bill keeps me from doing it. I just buy big rads to keep temps on my rig decent. Raddage is cheaper.