After reading a lot on this forum i started my own project a few weeks ago.
I used a "sandwich" panel as my back plate and some pex tubing to pump the water trough.
I have made a box of some old wood and insulated it with rockwool.
To seal it off i will use a double layerd polycarbon plate.
To measure the temperatures in the collector i will use a raspberry pi with the code of the website below. https://temperature-machine.com/
We will place the collector on the roof and the tank on ground level so it can drain back. I am not sure with pump to use and how to control it.
I am thinking of a snap-switch but i am not sure how that will go if there will be any condens in my collector. The other idea is to use a pv-solar panel directly to the pump. Can anyone advice on this?
First we where thinking about a spiral collector, but after reading here we decided it was not good for the winter weather.