How to change a burglar alarm battery

How to change a burglar alarm battery

Changing the battery in your burglar alarm is relatively straight-forward, and easy to do if you have a basic level of DIY skills. Here's a step-by-

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Changing the battery in your burglar alarm is relatively straight-forward, and easy to do if you have a basic level of DIY skills. Here’s a step-by-step guide to changing your home alarm battery:

  • Open panel: first remove the cover of your main alarm panel by unscrewing the screws holding the front of the panel on. The alarm will then sound. To silence the alarm enter your 4 digit user code.
  • Locate battery: now locate the alarm battery and remove the two terminals (red and black) making sure these don’t touch, and removing and replacing the battery. PLEASE NOTE, there is live 240V power in the transformer – so please be careful and make sure you don’t touch this. Also please make sure you don’t knock any of the other wires in the panel – as these may cause your alarm to stop working.
  • Replace battery: insert the replacement alarm battery, making sure you connect the red and black terminals back with the correct colours. If you get the colours wrong, this could cause a fire – so make sure you don’t get this wrong.
  • Close panel & reset: reset your alarm by entering your 4 digit code twice and press RESET. N.B. the exact procedure for resetting your alarm system may vary between different makes of alarm system – as all alarm systems are different.

How to video guide for replacing burglar alarm battery

Problems you may have when changing your home alarm battery

Although changing your alarm battery is relatively simple, you may encounter issues. Here are the most common problems you may have with replacing your alarm battery:

  • Alarm ringing when alarm panel lid is open: as soon as you take the front of your alarm panel off your alarm will most likely start going off – and drive you nuts! This happens if you don’t have the ‘engineer code’. Don’t worry, the best thing you can do is quickly replace the battery, close the alarm box and reset your alarm – this will stop the alarm from ringing. N.B. the reason the alarm rings is because there’s a tamper spring on the alarm box. You can push this in, and this should stop the ringing – however we’re recommend than rather messing around with this, you just get on and change the battery quickly!
  • Red and black wires spark!: DO NOT LET THE RED AND BLACK WIRES TOUCH – as this will cause the power to trip, and most likely blow a fuse (both in the alarm and also in the fuse spur – if you have one). In the worst circumstances this may cause a fire – so please make sure they don’t touch, or cover one with take (ideally the red one) to protect it.
  • Replace with the correct alarm battery: most alarm batteries take 12V batteries – with either 2.4, 3.4 or 7.1ah options. N.B. your alarm can take any of these alarm battery types, as long as they fit into the alarm panel box.

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