A fire department smoke ejector to replace a failed outdoor unit fan, in the center unit? That'll move some air!
I've humped those things up staircases and ladders many a time. Not used as much any more; positive pressure ventilation is the current "thing". Plus the PPV fan can be placed right at the front door. I like your use of it for this solution!
I have 3 of them and at home and the shop I use them to exhaust the dust out of screen less windows as I use clean/dry compressed air to blow out the nooks and crannies. 3 or 4 gasoline powered ones are on hand if I find a use. I used to be a volunteer fireman for quite a few years. Even bought the siren that I saw being put up in the early 70's Responded to that thing so,so many times.
