Yea……
I recently had the joy of moving my thermostat and timer.
Thankfully the boiler was installed with a terminal box with a wiring diagram in the lid so that end at least was easy.
But there were wires that went up into the ground/1st floor floorboards, then when I cut through what I assumed was the other end of the wire at the thermostat it turned out there was a junction box inbetween so just because I was holding the only T+e wire going into the void, doesn’t mean it was the same as the one coming out……
The plastic junction box was nicely earthed though even if the equipment the other side of it wasn’t wired up to it 😂
**** hell…
presumably it’s one of the sleeved ones coming in?