We have geothermal/UFH, had it for about 12 years and still not certain how it functions in some circumstances.
Each zone/room has a thermostat except the bathrooms which heat whenever the heat pump is working, i.e. if one or more zones is open. The system is not timed to operate and relies on the thermostats to switch on and off, this uses the concrete floors as heat stores to maintain and avoids repeated heating and cooling of the floors.
Hot water is provided using a large storage tank. This is heated 3 times a day by the heat pump, hot water then is drawn from a heat exchanger which heats incoming water supply as required and recirculates to the tank.
We have a wood-burning range cooker in the kitchen but haven’t used it for some years as it makes the room uncomfortably hot.
It is very expensive to run on electricity but the alternative would be oil or gas which we don’t have. Upside, the house is generally warm.