Sounds like the battery is life expried.
To replace the battery you will have to open the control panel and the anti-tamper will go off unless you have the Engineers code so in the absence of one here's what you do to get round it;
Obtain a new battery 12V & 2.1 to 2.8Ah is fine.
Open the control panel (the alarm will sound).
Switch off the mains supply (at fuse spur point).
Disconnect the battery.
Connect new battery (alarm will stop).
Switch mains supply back on.
Close control box (alarm will sound).
Enter your User code on keypad.
Press Reset. (alarm will stop).
The above worked for me in the absence of an Engineers code and saved having to pay £150 call out plus £80 for batery demanded by the rip off alarm company especially steep when only 10mins from their base! Instead just £23 for the battery!
Stephen, May 2010
