I have two mains smoke alarms installed in my house. They have both recently started going off for no reason. The only way I seem to be able to reset them is to flick the CU off the back on again. Where would these be wired into? Would they be wired in the lighting ring main or from the sockets? Any idea why they would be going off? I have an extractor fan in the bathroom that as recently stopped working. i.e. no power st ceiling switch. Could this have something to do with it?