WITH THE APU INOPERATIVE AND DEFERRED; POOR HAND SIGNAL COMMUNICATION BETWEEN FLT AND GND CREWS RESULTS IN FIRST PRESSURIZING ACFT AT THE GATE AND THEN THE LOSS OF ALL ELECTRICAL POWER WHEN THE GPU IS COMPLETELY SHUT DOWN RATHER THAN SIMPLY SHUTTING OFF PNEUMATICS TO THE ACFT.

Narrative

THE AIRPLANE DID NOT HAVE AN APU. WE WERE ON GND PWR AND HAD EXTERNAL AIR HOOKED UP. AFTER BOARDING AND LOADING ALL THE BAGS; WE WERE READY TO CLOSE UP. WE HAD AN AIR START THAT WAS RUNNING. I GAVE THE SIGNAL (ONE HAND FLAT; THE OTHER IN AN UP-AND-DOWN MOTION; MAKING A T) TO THE GND PERSONNEL TO DISCONNECT THE AIR CONDITIONING. HE ACKNOWLEDGED WITH A NOD. I GAVE HIM THE SIGNAL FOR AIR DISCONNECT AGAIN; WAITING TO SEE THE SIGNAL AS A RESPONSE; RATHER THAN THE NOD. SECOND TIME HE ACKNOWLEDGED ME WITH A REPEAT OF THE HAND MOTION. THE FO WITNESSED THE EXCHANGE. WE WAITED AND THEN GAVE THE SIGNAL FOR ENG #2 START; TO SEE IF WE WERE READY TO SWITCH TO AIRPLANE PWR. HE REPEATED IT. I ASKED THE FLT ATTENDANT TO CLOSE THE MAIN CABIN DOOR; IN ORDER TO RUN THE BEFORE START CHKLIST. AS THE DOOR CLOSED; OUR EARS STARTED POPPING. WE REALIZED THAT THE AIR WAS NOT DISCONNECTED. THE DOOR PAGES DISPLAY SHOWED THAT THE 'SRV' DOOR WAS YELLOW. I COULD NOT SEE IF IT WAS OPEN OR IMPROPERLY STOWED. I SENT THE FLT ATTENDANT TO MAKE SURE IT WAS CLOSED. AFTER THAT; THE 'SRV' DOOR POPPED OPEN. I QUICKLY RAN OVER TO THE OPEN DOOR. I SAW THE AIR CONDITIONING HOSE WAS STILL INFLATED. I GAVE THE RAMPER THE SIGNAL TO DISCONNECT THE AIR AGAIN. HE WALKED UP TO THE GPU AND TURNED IT OFF. WE WENT DARK WITH A PLANE FULL OF PEOPLE. I TRIED CLOSING THE 'SRV' DOOR AND COULD NOT DO IT. WE CONTACTED THE MAINT TO FIND OUT THE DOOR HAD BEEN DAMAGED.