Why is 'Cool On' or 'Heat On' flashing on my display?

The flashing 'Cool On' or 'Heat On' message means the built-in compressor protection feature is engaged. This feature forces the compressor to wait a few minutes before restarting to prevent damage from restarting too soon after shutdown. Wait 5 minutes for the system to restart safely, and the message will stop flashing when the safe wait time has elapsed. (Page 15, 19)