Boiler switch

jimmyw · 23-10-2011 5:05pm #1

I have just been trying to tidy up the switch on the wall, cause there was only one (Long) screw holding it in cause the installer didnt have a screw at the time.It has got a switch with a fuse.When I checked the continuity of the terminals, the switch breaks both the live and the neutral circuit.The fuse just breaks the live side.The box that screws into it is too thick, (hence the long screw) and the shape of the switch wouldn't allow just that to screw in without the box.
I have found another similar item, that will fit on its own,but without the switch, just a fuse.it works in much the same way except no switch.So if the fuse is pulled, the neutral will still be connected but not the live only.So why does the other switch need to have the neutral circuit disconnected along with the live? I thought that if the live is broken, then there is no power in the neutral either.Is there something i am missing? (apart from brains, I know:p) Would it be ok to leave it like this?

One on right is the original one

Marcus_Crassus · 23-10-2011 5:14pm

They're the exact same except one has a switch to isolate the appliance, or fixed unit in question (which's a boiler in this case).

The breaking of both the live and neutral is just for extra safety. It depends on what the application is; for some applications it's compulsory to break both poles. In fault conditions the neutral could become live...

DublinDilbert · 23-10-2011 5:19pm

It's a switched fused spur you have fitted.

You don't nessicerly need a switched one on a boiler, so the other one should be fine. The last two time clocks I replaced, both of them had non switched fused spurs.