Solar Air Heater Results

     Here are the promised results - kind of. For a few hours in the middle of the day, the thermocouple measuring the temperature of the air coming in the house didn't return a reading. I suspect that this is due to the fact that I never soldered them, so as it got warmer and warmer, the two wires separated. I'm going to solder the thermocouple today and take some more readings. I assumed that temperature stayed at least as high as right before it quit reading. I think it's a fairly safe assumption since when it did start reading again it was within a degree or two of when it stopped.
     I also think that the temperature is way too high. I'm sure that I am losing heat to the environment so I plan on installing another snap disc sensor to control three more fans. I'll have these fans turn on when the air entering the house exceeds 110°F and turn off when it drops below 90°F, just like the fans in the heaters. I'll install these at the air intake in the house, hoping that the additional air flow will keep the temperature of the heaters and duct work lower, but increase the overall temperature in the house. I also plan on monitoring the temperature in the room where all the air blows.
     My wife turned the heater off yesterday at 10:40am and back on after 4:00pm. That's one fifth of the day. I hope that correlates with at least one fifth of my gas bill. We'll see...

Solar Air Heater - Project Complete

     They're done! They're installed! They're running right now! What else is there to say?
     The scaffolding lifts them off the ground six feet. This should get me about two hours more of run time per day. I wanted to use one more set of scaffolding to get them up higher but I'm not sure it's worth the risk. If we have wind like we did November 20th, I doubt these will survive being as high as they are. This picture was taken before I finished ducting them to the house - minor detail that DIYers will notice, so I thought I'd mention it...
     Tomorrow I'll post the heating results from today - temperature in versus temperature out. In a month or so, I'll post the $aving$ realized for November/December - with one unit installed temporarily for half the time and three units installed for the other half of the time.
     The actual costs (not including taxes) for building each unit are posted below.