Installed a Takagi Tankless Hotwater heater, to serve as the heating system and as the hotwater heater for my domestic how water.
I used a flat plate heat exchanger to keep the fluids separate. The water comes from the well, into the tankless water heater, which turns on when it has flow of greater than .5 gpm. Then exits out to the house.
If the heating system calls for hot water, there is a small pump that circulates water through a small loop into the heat exchanger. this in turn heats up the water used for the floors. The pumps for each zone, floor 1 and floor 2, circulate water through the floors and through the heat exchanger.