I don't think a picture will help - I haven't wired anything yet! I am looking to install HIVE into an existing/working S plan set up. For additional clarity, I guess my question is stemming from the fact that on a traditional set up, programmer and room stat are separate units: programmer is connected to the stat, which in turn is connected to the zone valve (brown wire), so when both prog and stat are calling for heat, boiler will fire - if either or both are NOT calling, then boiler won't fire. It looks as though, from a wiring point of view, the HIVE receiver effectively rolls both the programmer and stat functionality into one - that's what I'm seeking confirmation on, not having fitted one of these previously. (To be honest, I can't see what else it can be, as there is no other device to wire in).