I think I know the answer so I'll throw both out there and see how stupid I am I have a FHW boiler that is only used for heat if we are away from the house. Currently this boiler also heats our hot water. We will be putting a 50 gallon electric hot water heater in late this month or early next month. Eventually, I want to have some sort of solar system that will heat the hot water in summer and help the electric heater along in the winter. Cut the supply line from the well to the boiler. Put a tee and tie the water heater in before the boiler. OR Cut the hot supply coming out of the boiler and tie in the water heater to that line. Is either correct, are both correct, is there a better way? I will put valves and capped ends on tees or four-ways so I can tie in later with the eventual solar system. As a "bonus" my electic box is full Time for a sub-panel.