Hi All, My first post on this forum (although viewed for a few years) so please go easy on me. My mate today gave me his Nest Gen2 thermostat and Heat link as he has upgraded to Gen3. Initially I thought this would be a simple swap for the existing thermostat until I realised the heat link needs wiring into the system. After reading all day I am viewing so many mixed ways to install that I feel I may be over complicating/ thinking this. And after speaking to a local plumber 'apparently' this cant be installed on my system (although think he couldn't be bothered. I have an Alpha boiler that is sealed for central heating and hot water is provided by a cylinder. The system communicates via the 'Drayton' programmer and the 'Honeywell' thermostat (wired). All the wires lead to and from the junction box that is in the airing cupboard. Now I Believe the Heatlink has to sit next/ near to the junction box and requires wiring for Live & Neutral, 'Call for heat' (terminal 3 in 3rd photo) and the common wired to live (terminal 2 in photo). Now upon opening the junction box I am met with the below (quite tidy) and wondered if the above is correct and which cables I should use to connect to the heat link. If you believe I may be out of my depth than please say so, but it cant be that hard?