Yeah, the more I think about it, the more I think a temperature based solution is the way to go. You're reacting to what is the current state, rather than trying to regulate an input.
Hi! My first post, so I'd like to introduce myself and ask some advice. I'm English, have a house in Sheffield in the UK and also a holiday home (fixer-upper) in the south of France (about 15-20kms from the Med, near Beziers).
Unsurprisingly, it's the house in France that has the solar...
No problem, glad to hear differing views. But I'm very happy with the arrangement we have at the moment just want to tweak it a bit. I still have unused real estate on both roofs so the addition of more solar PV is definitely in my plans.
As a temporary solution to the problem (while I decide on a longer term one) I've put together a wooden box that fits snugly over the solar array that drives the pump. I cover the solar panel about half an hour before sunset and remove it around 10:30 am (this will change as the year progresses)...