I have an Astec alarm and in the last couple of days it has been going off - even when the alarm hasn't been set on! It is about 9 years old and I replaced the back-up battery in the main panel in the house last year. Is there also a back-up battery in the bell box which should have been replaced? If I switch it off at the fusebox and disconnect the back-up battery in the main panel will this stop it going off while I find a fix? It has gone off twice this evening for no reason and I don't want it going off during the night! Can anyone please advise?