I am in Corfu, Greece and have a Biasi Riva 24 Combi boiler. I fitted a Drayton room stat (bought from B&Q in England) and the temperature is way out (when the dial says 12c the room is at 18c). There is nothing in the instructions for altering the settings. I have bought an Olympia Electronic BS-900 locally to replace it (if I can't find an adjustment) but it shows 3 connections and the Drayton only has 2 - any help, please. Kev.