Preheating for check-in
Rooms warm early enough to be ready — automatically, using the weather.
You don't set a "start heating" time. The system judges how early to start each room so it reaches comfort by check-in, allowing for how cold it is outside.
On a bitter day it starts earlier; on a mild one, later. For function rooms you can give a longer lead so a large, cold space is fully warm as guests arrive.
If a specific room is regularly a little cool at arrival, tell your manager — its lead time or radiator sizing may want a look.