The heating timer or programmer lets you control what times your heating and hot water comes on. You can use this to set the heating to come on just before you wake up, just before you get home from work, or whenever else suits you best.
The thermostat lets you set the heating to the temperature that you’d like. If you’d like the radiators to be set at different levels throughout your home, you can adjust the thermostatic radiator valve which can be found on each radiator. This will allow you more control over the temperature in each room. We've got a how-to video which shows you how to do this here.
If you don't want to use the timer, your heating can be controlled by adjusting the main thermostat.
It's not a good idea to completely turn a radiator off in a room for long periods of time as this can lead to damp and mould issues. Learn more about damp and mould and how you can prevent it from appearing in your home.