As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LOW AIRFLOW FROM OVERHEAD AIR GASPERS. RAN AIRCRAFT AND THOUGHT IT WAS LOW OUTPUT FROM AIR COOLING TURBINE. SWAPPED AIR COOLING TURBINE WITH LIKE UNIT FROM ANOTHER AIRCRAFT. RAN AIRCRAFT AGAIN, RESULTS WERE THE SAME. TROUBLE SHOT SYSTEM AND FOUND GASPER PRESSURE REGULATION VALVE WAS STUCK IN THE ALMOST FULLY CLOSED POSITION. REMOVED VALVE FROM AIRCRAFT AND FOUND EXCESSIVE CORROSION ON THE VALVE ASSEMBLY. REPLACED VALVE, REINSTALLED ORIGINAL COOLING TURBINE UNIT, RAN AIRCRAFT, SYSTEM OPERATES NORMALLY. RETURNED AIRCRAFT TO SERVICE.