What was found
BOI - FLIGHT 2202 - THE AIRCRAFT RETURNED TO FIELD TWICE WHEN AFTER TAKEOFF THE AIRCRAFT FAILED TO PRESSURIZE. ON THE FIRST RETURN, MAINTENANCE FOUND THE PRESSURE REGULATOR VALVE STICKING. REPLACED THE VALVE, PERFORMED OPERATIONAL CHECKS, AND RETURNED THE AIRCRAFT TO SERVICE. WHEN THE AIRCRAFT RETURNED BACK TO THE FIELD, MAINTENANCE INSPECTED THE AIRCRAFT AND PRESSURIZATION SYSTEMS AND REPLACED THE FLOW CONTROL SERVO. OPERATIONAL CHECKS WERE GOOD AND THE AIRCRAFT WAS RETURNED TO SERVICE.