Just need confirmation I am using the correct cable between the thermostat and switch. Presently using 2.5 2 core + unsheafed earth. Nort sure why the earth is unsheafed.
The correct flex that you need to use is 1,5mm 3core Butyl flex as it is heat resistant and flexible.
PVC twin and earth cable, when heated becomes brittle causing the breakdown of the insulation therby exposing bare cablel to the touch
goodlooking is 100% correct, on no account use ordinary cable, it must be heat resisting. long time since I heard it called Butyl, goodlooking you must be as old as me,