When does a burglar alarm battery need replacing?
A burglar alarm battery needs replacing when the keypad shows a low-battery or fault warning, the system beeps, or false alarms start, often after a power cut. The control panel has a backup battery, and wireless sensors have their own. An annual service tests them all and replaces any that are failing before they cause a problem.
Which batteries does a burglar alarm have?
A wired alarm runs from the mains, with a rechargeable backup battery inside the control panel. That battery keeps the alarm working during a power cut. The external sounder usually has its own battery too, so it can still sound if its cable is cut.
A wireless alarm adds a battery in every sensor, door contact and key fob. These last a long time, but they do run down, and the system reports each one when it gets low.
What are the signs of a failing alarm battery?
The keypad or app shows a low-battery or fault message, often with a regular beep. The alarm may go off for no clear reason, especially after the power has been off, because a weak backup battery cannot hold the system steady.
An alarm that sounds in the night without a cause is very often a battery. It is worth acting on the first warning rather than waiting for a false alarm.
Can I replace an alarm battery myself?
Sensor batteries on some wireless systems are designed to be changed by the owner. The panel and sounder batteries are different: they sit inside housings protected by tamper switches, so opening them sets the alarm off unless the system is first put into engineer mode.
For that reason panel and sounder batteries are normally replaced by an engineer, usually during a service. Locks & Alarms Ltd has verified battery replacement jobs in DA5, DA8, DA15 and DA17. After one service visit in DA17, a reviewer wrote: “My alarm is now back working”.
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Related service: Burglar Alarms