The heating/hot water system is most efficient if the hot water in set to always on. The Heating should also be set to always on too. Though in the Summer you may choose to turn it off. The room temperature is controlled by the Google Nest Thermostat E.
To control the Nest thermoset you need the nest app from the app store or google play from
The best way to use the Nest thermostat is to set the temperature you require at a given time.
For example.
You can set
Midnight to 06:00 15°
06:00 to 08:30 20°
08:30 to 17:00 17°
17:00 to 22:30 20°
22:30 to midnight 17°