I recently tried to find our manual for our “British Gas RC Plus Termostat” on the internet as we have lost our original manual.
Anyway, after some research, I found they British Gas just re-badged them from Drayton Digistat and here is the links to the pages that contain the .pdfs’.
http://www.gasapplianceguide.co.uk/DigistatPlus2.pdf
http://www.draytoncontrols.co.uk/WorkArea/DownloadAsset.aspx?id=4235