Sorry, I haven't updated anyone on the solar thermal rig. Since the end of the Rona restrictions, I have been buried in real money paying work. Nonstop people trying to throw money at me to catch up the shortfalls.

The one I built last spring is doing great. I was concerned about evaporation and thought I would need to fill the tank to keep it from steaming out. Nope, we get more than enough rain to keep it topped up all year round. While I was somewhat logging temperatures manually, the collector kept the tank in the 130 to 150 degF range in days when it had direct sun exposure. I rigged a little giant pump to a klixon thermostat so it ran when the collector got above 80 degF.

The larger one is still in the garage waiting for me to work on it. Not going to use the steel stud channels on it, they're too flimsy. The RV water pump that is going to supply both panels moves a lot more water, at higher head pressure, than the little giant in use now, so it will need a new control strategy.