Sorry for the delay. Here's the final version of collector I recently photographed. Unfortunately I didn't get great pictures of the intake etc. I'll be building one this spring. If you look carefully you can see the inlet at the bottom right in the collector. It has the same thermostat as his second collector, but this one finally adds in a return air inlet to cylce cool air off his basement floor into the collector. It probably isn't balanced air in and out but its a lot better than over presuring the house! This is the return back to the far end of the collector. I had more pictures but they didn't work out. All his collectors are only single glazed glass and they aren't even sealed between the panes of glass!! In fact there's a notable gap between the panes. I wonder if a double glazed low E window would work better?