Another quick updated. I cut a hole in the insulation that I stuffed into the hole in the kitchen's chimney. I got the wire run down for the kitchen temperature sensor. I also made a damper for this hole. As you can see, it holds itself in place quite well just by the pressure of the air wanting to escape! So, a damper (or more) is REALLY needed otherwise I'll loose all the precious heat I'm trying to get.

http://ecorenovator.org/pictures/house443.JPG


Super fancy damper! I'll stick it in place with something so it doesn't fly off. In the picture, the hot air trying to escape up the chimney was enough to hold it in place quite well.
http://ecorenovator.org/pictures/house444.JPG

Next step was getting power to the fan setup. I had to add an outlet for it.

http://ecorenovator.org/pictures/house445.JPG

I've still been working on the system. Mostly, I've been troubleshooting little issues here and there. The switch from the benchtop version of the arduino differential thermal controller to the working version provided some hiccups that I'm still working out. While I was tweaking things, I also compensated for the resistance in the long wire run in the programming. Its too bad too, yesterday would have been a perfect day to run it.

Well, I found out one of my temperature sensors got fried. I think the wires got crunched together and it shorted out. I thought I had an extra on hand, but apparently not. Now, I have to wait for new ones to arrive...

Well, I got tired of waiting (and having many good heat harvesting days wasted). I came home today to a 93 degree attic! So, I setup the controller a little differently. It currently does not monitor the kitchen temperature. Once the attic gets to 23C / 73F it kicks on. Once it drops to 21C / 70F it kicks off. That is above the temperature the house is kept at (20C / 68F).

Currently, I am monitoring my kitchen's temperature to see what effect the fans have.

As for noise, there is a bit of electric motor hum that is coming down the chimney and the sound of rushing air a little. However, its quieter than when the furnace kicks on.

Well, it works. :)

Here is the logged temperatures. There are a few notes to go with it. Between 7:15 and 7:30, we were in the kitchen preparing diner, thus the temperature bump up where it had previously slowed. Also, after 8:00 I manually shut the fan off to see if the temperature decreasing trend would increase, and it seems that it did. Also note that the later time periods are not equal.

Here is a nice image to show what I mean.

http://ecorenovator.org/forum/attach...1&d=1302748687

So you're getting an extra 3°-4°F from the attic. Good job!
Does the warmer air from the kitchen also raise the temperature in other rooms?

I kind of watched my thermostat in the adjacent room. It did not seem to be effected by it much.

Very cool, Tim!!

That's awesome. You're using the roof as a solar collector.
In summer will you run the fan in reverse to pull hot air out of the house and into the attic?