National Instruments Labview with a small PCMCIA data acquisition card for my notebook is the control and monitoring system. The software graphs the data from the whole day, and adjust the flow control valves to provide the best mixing of flows for the heat sources that are active at the time. It is not uncommon for the 4 heat storage drums and the hot water tank to be at 150-170F all winter.
Better photos of the heating schematic:
and the labview control software:
Labview control software