More than 2 hours –
I built my own cooler some years ago, but it does not use the vortex method. I am thinking of redoing mine next year using the vortex configuration. I'll tell you why. Mine pushes the smoke straight through, which means the ice receives direct heat in the first half of the cooler. This reduces the life of the ice and we have to refill the cooler every two hours.
The vortex reduces the direct exposure to the heat throughout and provides a lot more cooling surface because the smoke is wrapped around the ice several times. Great idea, and should result in ice lasting a lot longer (sure beats the hell out of dry ice!).
Just because I am old and I like to reminisce, I once used a dry ice cooler that was made from an industrial trash contained (those big things you see at restaurants and businesses). There was huge heating elements in the bottom of this thing, and it took 220V/100A to run it. It was a beast! But man did it put out some fog! We could fill an ice arena in a blanket of fog in about 10 seconds!
Travis "Big T" Russell
Big T Productions Inc
Owner and Operator of "The Plague" and "Camp Nightmare"
Customer Quote of the year: "Damn, I pissed myself"