Help Center1) Remove the power transformer & backup battery (in that order, wall plug should be unplugged from the wall and then the battery should be removed) so there is no power to the Vista Panel's control panel. “To verify this make sure there is no power to your keypad”.
2) Next, you can power your Vista Panel back on by first plugging in your alarm backup battery followed by your transformer within 40 seconds and you should see AC or D1 on the keypad.
3) Press and hold * and # for three seconds on the programming keypad from there you should see INSTALLER CODE 20 or 20.
4) Press *20 4112 (You should here 3 beeps) this will indicate that you have successfully reset your Vista Panel's installer code.
Once you have competed any programming necessary you can press *99 to exit the programming mode of the Vista Panel
Programming Manual For More Information
GeoArm can assist in changing the installer code upon activation.