Thanks RF
Yes there's a neon on it. Will try for a piccy and get a clearer description of the yellow and black wired loops on the back of the faceplate.
Ta again
Hello, please help with my query re. blown FCU.
FCU connects underfloor heating in bathroom along with it's timer/stat (Devireg 540). System has worked well since professionally fitted 4 years ago. Supplier seemed to think fault can't be with Devireg system as "nothing to go wrong". Upon...