When we heat our house, we also heat water through the mason stove using a 3/4" copper pipe. Circulation to the boiler is activated at 70 degrees Celcius through a bi-metal switch. (The water needs to be above 60 degrees Celsius to avoid condensation in the fire chamber.) The pump only switches on intermitently when the water in the stove is hot enough to contribute to the hot water tank--minimizing energy use. We have a mixing valve on the tank for safety to mix hot water from the boiler + cold feed water.
