Thanks for the replies, much appreciated. Bit confused why you think I have shown wiring Diagrams for the thermostats though Ianmcd? What I have shown is the actual receiver backing plates and the programmer wiring diagram. I have put them against the thermostat boxes, just so I know which is...
So I'm looking for some reassurance before I blow up my boiler and lose all heating whilst it's snowing outside! I have searched and found similar setups but nothing that matches mine enough to give me that confidence!
I currently have a 3ch ESI3427B Programmer controlled by 2 x ESI ESRTERFW...