The Vista systems can record up to 100 system events in a history log. Because you have an Event Logging selection is made in field ∗90, a message was sent to the central station when the log was 80% full. If the log becomes full, new messages overwrite the oldest messages in the log.
To disable this
1. Enter Installer Code 4112 then 8 then 00, keypad should display "20"
2. Press *89 then enter 00, keypad should beep several times
3. Press *99 to exit programming