No green LED light kidde firex kf10

[RPCodie]

Last October (2017) I replaced 3 oldish fire/smoke-alarms with 3 Kidde Firex KF10. All have functioned correctly until one day ago, when the alarm at the top of the stairs within the loft extension failed to show the green LED. I checked the local fuse box & no evidence of any tripping, and the lights (on which I assume this to be connected) were working correctly. I have removed the alarm from the ceiling, but cannot see any obvious fault, & have checked the wiring back into the ceiling for loose connections. Depressing the "hush button" gives the necessary short alarm note. the other 2 alarms have the green LED on. As a red herring, my wife heard a distinct "clunk" around the time the alarm failed in the area where the alarm is situated, and temperatures have been pretty high in the roof space.

Any thoughts/ideas/suggestions?

Many thanks

[green-foam]

You need to check the supply to see if there is mains there.

The other thing is what happens if you swap smoke alarms? does the one with no green light now have a green light? and the one that had a green light have no green light?

[Guest Tduf]

Question please, the maintenance guy replaced our old fire alarm because it kept going off , the old one had a green light solid, this other one he replaced it with has no green light or any other light? Is it a real fire alarm? He took this one out of his apartment?? The one in hall upstairs still has a solid green light 

[green-foam]

Without seeing it, it is not possible to say, but my guess would be that it was a mains powered smoke alarm, and now it is a battery operated smoke alarm, the downside is if the smoke alarms were interlinked (So that when one goes off, they all go off) they will not now be interlinked.