For all the naysayers: C&P'd from Google
"My house has 3 gable vents, 2 large (30" h x 60" w) and 1 small one,
so, since I own an HVAC company, I have access to a large number of
motors, so I decide to take a motor/fan combo from a unit I had just
and since 220 volts uses less juice than 110, that's what I used, might
not be a
good choice for tha DIY'er, but could be, so after installing my fan
and wiring it
up, I checked the intakes and man were they suckin or blowin, which
ever it was movin
So I proceeded to maximize my heat remover by closing off the space
around the fan and other vents that allowed air to escape to quickly,
so after all
was done, I believe I dropped my heat gain by 1/2 to 1 full ton..... "
Next, he might try 110 VAC.