As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HOT AIR MIXING VALVE WAS OVERHAULED BY ROCKER, 1-25-05, REF WO 56559. INSTALLED IN AIRCRAFT FROM STOCK ON 6-4-05. DURING FUNCTIONAL TEST FLIGHT FOR PRESSURIZATION PROBLEM, THE UP STREAM FLANGE SEPARATED FROM VALVE HOUSING. RELEASING BLEED AIR INTO AFT EQUIPMENT BAY. AFT FUSELAGE HOT LIGHTS ILLUMINATED. FLIGHT ABORTED. RED RUBBERIZED INSULATION MELTED/BURNED AWAY NEAR LEAK. POST FLIGHT EVALUATION REVEALED FLANGE NOT WELDED/BRAZED TO HOUSING.