What are these in every room

[iTRYer]

Aha. Thats tells a lot. there is nothing connected to those two. There are cables connected to the feed IN terminals, but nothing on the output side. Its possible that you could change the FCUs for sockets, but need to do some checking first.

Your next task is to check if there is voltage on the L&N feed wires (do you have any test gear, a multimeter will be ok.)
If there is voltage there then you need to find out what size fuse or MCB protects the circuit (or circuity).

Agh thanks, so I assume the centre connection on the boxes is the output and they are both empty...so feed in and nothing out so they can all be off for now. I will check voltage think I have a MM around, maybe they were old electric rads...or something.

 

[bsr]

As per one of the first comments, likely to be old storage heaters or electric radiators.