Our house is new construction built in 2005. About 6,500 sq ft. We use two Geothermal Heat Pumps - one water to air for A/C and second floor heat and one water to water for radiant heat to first floor, second floor master bedroom/bath, basement and garage. The water to water unit also preheats the domestic hot water and is supplemented by a Bosch tankless propane water heater. We also have a hot water recirculation system currently set up with a timer and thermostat.
As you can see from my graphic the monitoring system is still under construction and I will continue to add sensors, etc. (So much fun -driving my wife crazy!)