EMPLOYEE WAS WORKING ON LINES FOR INSTALLED PRESSURE WASHER. HE LOCKED OUT THE UNIT AND DISASSEMBLED LINE. HE REMOVED PRESSURE WASHER MINIFOLD - COMPUTER-ACTIVATED VALVE OPENED AND RELEASED STORED PRESSURE FROM LINE. PRESSURIZED WATER STREAM STRUCK EMPLOYEE IN LEFT EYE (ABRASION/IRRITATION OF EYE). HE WAS NOT WEARING SAFETY GLASSES.