Thanks for the replies.
I have set it to "timer" on the right hand side.
I'll try setting the temperatures as you say.
It is possible that it is wired slightly wrong as I dont have the boiler instructions.
Its a Worcester 24CDI.
Installed it myself. Commisioned satis. Set the times on the stat to my own ok.
My problem is-it turns the heating on whenever the temperature falls below what is set on the stat, reguardless of the timer settings. Basically as if it is on all the time. Any advice welcome.