Solar heat box

[Slow1]

One thing that confuses me on these collectors - I see that folks put the fans pulling the hot air out of them. Yet we often preach that it is "better to push cold air to the stove". It would seem to me that perhaps some of the same logic may apply in terms of being easier to push dense cold air into the collectors than to pull the 'thinner' warm air out. Can anyone explain the logic here? Is there any particular logic one way or the other?

 

[woodgeek]

I think for a closed system like these air collectors, it shouldn't matter (except the fan will run hotter). I think the main reason why blowing the cold air to the stove makes so much sense is simply that 99% of the time fans go on or near the floor, where the natural cold air return is flowing anyway. If we put similar fans blowing sideways on our ceilings, I bet we would find that they work well blowing away from the stove. Of course, those little doorway fans come to mind, but I always thought most of them were far too small to be worth messing with.

 

[karl]

Has anybody built a large one or a serious of small ones and posted a website about them? I'm talking a hundred square feet of collector or more. Maybe even placed on a roof.

 

[fishingpol]

check out builditsolar.com