How to Reset a Home Alarm After a Power Outage

Many homeowners install alarm systems to ensure that their home is protected from intruders at all times. But if your home experiences a power outage, the lack of AC power could leave your home temporarily unprotected. To avoid this problem, modern home alarm systems often include a backup battery function to prevent the electricity to your system from being disrupted during power outages. However, even with a backup battery, some alarm systems may display an error message after the AC power comes back on. You'll have to reset the system to clear the error message.

Step 1

Locate the "System" or "System Status" button on your home alarm keypad. Press the button twice, in quick succession, to silence the "No AC Power" alarm.

Step 2

Wait until the AC power is restored to your home. Take the system's backup battery out of the alarm keypad.

Step 3

Lift the cover of the circuit breaker box and find the breaker that controls your home alarm system. Move the breaker into the fully "Off" position; flip the breaker back to the "On" position after five minutes have passed.

Step 4

Replace the backup battery in the home alarm keypad. Install a brand new battery, if desired; note that most home alarm manufacturers recommend replacing the backup battery every 12 to 15 months. Install a new battery any time you get a low-battery message on the alarm control panel.

Step 5

Enter your user code into the home alarm keypad; press the "Off" button. Re-enter your user code and press the "Off" button a second time to reset the alarm system.