Simplified Solar Hot Water

Author	Message
Murphy's friend Guru Joined: 04/10/2019 Location: Australia Posts: 671	Posted: 07:42am 05 Jan 2025         azhaque said   Great to know that yours is running flawlessly for 2 years now which must be satisfying for you. Tuning has been used generically by me in the sense that setting up of the trip points may require a couple of iterations by way of soldering/desoldering R1 and R2. I assume that you had to do it too, although you haven't mentioned it in your build. azhaque Hmmm, have another look at the schematic I posted at the thread above. You'll find that there is NO soldering/ unsoldering of resistors required. Instead, two trim pots are adjusted to set the trip points. To recap the requirements; use a water heating element that matches the medium solar panel string voltage AND power. Use an adjustable DC power supply instead of the solar input to set the trip points. I used a makeshift arrangement of rectified mains voltage and capacitors, the mains voltage being adjustable with a variac. This is much easier than trying to use the solar input to adjust this project. Have a read of my post to check how it's done. It's your choice if you wish to complicate a simple project with more electronics but I can guarantee you that there will be no magic increase of water heating power.