Definitely green and yellow it does look like it's sleeved. on the dt90e you do not need a neutral if I marked it appropriately could I use the blue wire as the switched live
I have a manual dial thermostat that I want to change to a Honeywell dt90e the wiring is as follows red to No1 yellow/green to no3 blue to no4 is it possible they have used the earth wire as the switched live as the blue is the neutral
