accenta g3?

Hi
Can you help, I have an accenta g3 alarm. The alarm was triggered by mistake but would not reset from the panel. We had to turn off all power I have now managed to get the system up and running ok, by replacing the back up battery. Providing I omit zone 8 on the panel the alarm will set and operate correctly. Is there any way I can set zone 8 to be permently ommitted. This zone is not used at all, not connectd to any sensor