Sounds like a lot of work..
But, I've been thinking of another way to harvest some hot air..
My attic does get pretty warm when the sun hits it.. So,,
Sorry about the pic (made in parts).
There is a pretty powerful exhaust fan up there.. If I could channel that hot air
into some 3" x 4" plastic downspout, and spray it into the air intake of the Sanyo..??.
Seems like it might work..
Even if the air was only 10 or 20 degrees warmer than outdoor air temp,
it might help save some kWh and keep down the number of daytime defrost cycles.