Cheers for that. Looks like Red in A and Yellow in B. Get rid of link, make the neutral and earth electric safe. Switch system off at breaker before starting!
Looking for some advice. I wish to change the old BG analogue thermostat that is located in out hallway and replace with a Honeywell DT90E. I understand the Honeywell will only use 2 wires, the original live red and the original yellow switch....... So I removed the front of the old thermostat...