If you don't want to use it you can disconnect the power to it by removing the fuse from the fused spur that supplies it (it is normally a square white plastic box with a small fuse holder in it which you can unscrew to access the fuse) There ought to be a backup battery inside the control box which you can also disconnect after you've disconnected the mains power (pull off the two battery leads). You MAY also have a battery in the external alarm box on the wall - but unless you want to go up a ladder to disconnect that you'll have to choose your time and then let it ring the bell till it has flattened itself! Then you can have peace!
Richard
January 2009