If your Simon XTi panel is beeping and you don't know why, it generally means that there is a trouble condition that needs your attention.
Step By Step Instructions
Here are the step by step screen shots as well for your convenience.
Press the gear icon.
Then press on "Listen" next to Panel Status. Once your panel starts talking press "Clear" to erase all old memory in the system.
Then press "Listen" again and it will tell you the current status of the panel.
Simply listening to the status will stop the trouble beeps for the next 4 hours. You can find troubleshooting information for any current problems right here on our online Help Center to get the issue resolved in the meantime.
If you are not going to be able to get the trouble condition fixed for a while you can stop the beeps indefinitely by turning off the Trouble Beeps.