Solar shop heat redux (badly)

[ironhat]

Well, I tried an admittedly cheezy solar heating experiment - a far cry from the thermosiphon which I queried about in a previous post. I painted a piece of flashing flat black and backed it with a piece of corrugated cardboard. I then mounted it in a garage-shop window, 2" from the insulated panes in a double hung sash (roughly 24" x 44"). A 2"opening on top and another on the bottom and the thing will bring the temp up 4* in a 336 sq ft area on a sunny day. Evening temps are in the teens and daytime temps in the low to mid 30's, mostly sunny, but as the days cloud over I'm slowly surrendering to the thermal flywheel of the equipment. So, what's the consensus? Not enough mass in the flashing? Too much glare from the glass (not low-E)? I had planned on a thermosiphon protruding from the bottom of the window at an
angle about equal to our latitude ( http://www.motherearthnews.com/libra..._Heat_Grabber_).
Unfortunately, time, money and health have me doing this poor substitute.
TIA for your thoughts!

[thekon]

thanks for posting the link.....i've been looking into buying or building something like this for my garage. I don't know much yet about these heaters but i don know from what i've read that the newer materials for the solar catchers do work better than just flashing painted black. here's on for sale i've seen but it's a bit expensive for those of us on a budget.
http://www.hotboxsolar.com/solar2.html
also here are some more free plans for other collectors i've found
http://www.builditsolar.com/Projects...ce_Heating.htm

[ironhat]

Yep , a little on the steep side. Polycarbs are petty stout stuff from many respects, if ya get my drift. I really thought that I'd get more than a cat's exale from this unit and that someone would have an inkling why I'm not. On your 1st link you might check out MrWhipples, thecon. Thanks for the post back.
Later,
Chiz

[thekon]

First off.....Mr Whipples? didn't get the reference but then i've had a long day at work!
Second, after doing some more studying.....your inlet out lets sound small, are they 2 inch in diamater?

[thekon]

oops, didn't mean to post, wasn't finished........ You might also try posting in the mother earth news forums......they might be of some help. I hope to build or buy such a unit this winter althought I won't have insulation in my garage this winter, i hope it'll at least make it useable. You might also try to get some help via mother earth news forum or freecycle or such.....you might be able to get a few people together to scrouge parts and build some for everyone. Also I might mention a friend of mine built a decent size green house for 250 dollars.......how? He got all his glass for free.......he contacted glass companies and most remove old glass patio doors and such and just toss them out.....he found one that was more than happy to save them for him. It looks like a large building made of patio doors but it works! later,
Konrad

[ironhat]

Sorry 'bout the Mr Whipples. It's the second or third site on the one link you provided and it should have been jrwhipples, if I recall correctly. I posted to a newgroup and was told that give the size of the collector it was all I could expect. I could make a 4'x8' collector and narrow it at the window attachment and use a fan to overcome the bottleneck but I would need 1) more cash and 2) better health and 3)more time (spending more than we thought after moving Mom and Dad to a retirement home closer to us - NO complaints whatsoever!!!!!). I'd sure like to hear how you and, I believe, Steve, make out with your collectors. I'll watch for your posts.
Later,
Chiz