The system has several unique new wrinkles:
The tank is a relatively small footprint but is relatively tall and holds a good deal of water. It is the plywood box, framed with 2X4 perimeter frames at 4 levels. The tank uses internal polyiso insulation and the standard EPDM liner.
type of differential controller that John C. sells on his site as a kit. The pump and controller combo are only about $100 total.
With some good design and creative scrouging, Denver managed to keep the total cost of the system to $800 -- this is about 1/10th of what equivalent commercial systems cost!
All the details on Denver's $800 DIY Solar Water Heating System ...
More examples of $1K DIY Solar Water Heating Systems here...
Thanks to Denver for sending this material in!