Welcome to the Solar Collector
Brainstorming and Development Page!



Hot Air Collector

Hot Water Project 1

Hot Water & Space Heating

Solar Electric

Solar Construction 101


Best Collectors

Simply Solar
Sign up Latest Topics

  Author   Comment  

Posts: 10
Reply with quote  #1 
Hi All

I am making a 4x8 collector in Madison, WI and had a few questions.  I wasn't seeing the answers on the forum.  I am very excited about this project.  I have been neglecting responsibilities and reading the forums to gather as much info as I can.

1. Eo I need to put insulation on the sides of the frame?  considerable increase in efficiency?  I'd have to buy another sheet of polyiso to cut down to do this.
2. Has anyone considered 2 inches on insulation vs 1 inch?  results?
3. should the supply and return holes be 6" or 4", and on a vertical collector do they always go in the middle?  I was watching videos and some people, like Scott I think, have them in opposite corners.
4. 2 layers of screen or 3?  Is there a definite answer here?
5. does a 4x8 collector that lays on its side do just as well as one that is upright?  it seems like the natural convection would be easier in an upright model.
6. currently i am just using polyiso for the backing, and not a piece of plywood behind that.  is this good practice?  is there a way to do it better?  




Posts: 149
Reply with quote  #2 

First, welcome and good luck.  I will chip in my 2 cents here with what I think...we seem to be like minded (thrifty) based on some answers...no need to spend money we don't get back somehow ;-)

1.  I would insulate the sides as there can be a lot of heat lost there.  I notice a substantial increase in my water temps with my water unit, so didn't even try not doing side on my air unit. If you want, you could reduce the dimensions of the box to be inside the frame and have a back.  You could make it a couple of inches shorter and narrower so that you can use one piece of insulation. 
2.   no idea
3.  Given the choice, I would go with the 6 inch.  I used 8 inch on my larger collector and I really glad i did. The bigger, the better and the less velocity you need.
4.  On my screen collector, I used 2 layers and was happy...until I read come of the tests others have done making me think that 3 would be more efficient.  I used 2 in the back and one in the front of my Zero Pass collector.
5.  My research made me think that centered holes were more efficient at moving the heat evenly when the orientation was vertical, but offset if laid on the side.  I ended up using a 3 channel in my 6 foot high by 12 feet long air collector.
6.  If you can handle the weight, I would put a plywood back on it to be stronger and less likely to bow under pressure.

Just my simple opinions...I am sure someone smarter than I will come along eventually and give you more facts.  It is a little slow right now...I don't know why, I expected this to be busy today.


Posts: 10
Reply with quote  #3 
Thanks Bruce for your comments.  Here is a video of what I have done so far.

Previous Topic | Next Topic

Quick Navigation:

Easily create a Forum Website with Website Toolbox.


web statistics