Hi Just moved into a new house, where they have an old Worcester oil boiler and an S type system with port valves, thermostats and a Honeywell programmer. I’m upgrading to the Hive dual system. I’ve done similar before but the old wiring seems a bit of a pickle. They have a second mains feed going back to the wiring box, odd. Here’s some pix - I’m just going to use the originals wires from the programmer, shorting it the old thermostat, I’ll try and trace thru the old wiring box, does it look OK? Cheers Steve