The system shuts down if one of the following is true:
- The SBH or VZC shut down the system.
- All zone controllers are offline.
- The system is shut down via BI-1 at the IOM selected from the SBH when the Emergency Shutdown BI is enabled.
When the system shuts down, the RTU turns off the heating and cooling. The supply fan is turned off and the zone dampers close. The system restarts when the above conditions are returned to normal operation.