We had one Fantastic Fan installed in our '72 two years ago, and liked it so much we had another one put in last year. Now there's one front and back so we can really move the air if necessary. These fans are a real Godsend when you're camping in the summer without 30 amp electric. We have also used ours during travel in order to pressurize the trailer and reduce dust infiltration. This is something the manufacturer supports and recommends! We have traveled thousands of miles at 55-70mph with our fan running and the vent lid up in the uppermost position. We purchased the ones with rain sensors that close automatically and they really are hassle-free. Our first fan developed a fault in an electrical component which they replaced for free when our second one was installed.
Bonus: If you go to the International they have a team of installers working every day and they do a great job, saving you a lot of sweat and blood! And I think it's a pretty reasonable charge to install, but I can't remember the exact number. It was worth it to me not to have to cut aluminum on my trailer!
Downside: You'll loose your lights which are integral to the vent cover on most vintage Airstreams. We got around this by installing a Thin-lite fluorescent which makes more light with much less battery consumption.
Dallas Peak, MD 'That 70's Guy!'
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