IM WORKING ON A SERVER ROOM AC SYSTEM WHICH HAS A CONTROL BOX WITH PRIMARY AND BACK UP SWITCH AUTOMATICALLY SWITCHES TO BACKUP WHEN PRIMARY GOES DOWN SO THE PRIMARY IS DOWN BAD COMPRESSOR WAITING FOR NEW ONE I HAVE UNIT AIRHANDLER AND CONDENSOR ITYS A SPLIT SYSTEM AIR COOLED SHUT OFF AT DISCONECT SWITCHED OVER TO SECONDARY SYSTEM PACKAGE AIRCOOLED UNIT RUNS GOOD PROBLEM IS IT WILL NOT SHUT OFF RUNS CONTINUEOUSLY HAS ACCUTEMP SENSOR T-STATS ALL CHECKED OUT WORKS ALL DAY NO PROBLEMS CUSTOMER SAYS THEY FIND ROOM HOT EVEY MORNING PRESS BUTTON TO RESTET BACK TO PRIMERY SYSTEM THEN BACK TO SECONDARY AND IT WORKS ALL DAY UNTIL IT GOES OFF IN THE NIGHT AGAIN OUT OF IDEAS THE ONLY THING I THINK IS HAPPENING IS THE UNIT IS CONTINUEOUSLY RUNNING AND TRIPPING THE INTERNAL OVERLOADS ANY THOUGHTS WILL BE BACK THERE IN THE AM NEED SOME IDEAS