What was found
SMOKE IN COCKPIT AND BUNKIE SMOKE ALARMS ACTIVATED WHEN AT FL320 AND LEFT PACK OFF AND TEMP CONTROLS TO FULL WARM. COULD NOT DUPLICATE WHEN AT 10000FT. WHEN REPEATING TESTS WITH RIGHT PACK OFF, THERE IS MUCH LESS SMOKE AND BUNKIE SMOKE ALARM DOES NOT ACTIVATE. SMELL IS LIKE HOT PLASTIC. NO SMELLS DETECTED ON GROUND, START, TAKEOFF, OR CLIMB. FOUND MOLTEN DEBRIS IN DUCT AT LT E&E TUNNEL AT STA 188. SENT RVI PICS AND CLEANED DEBRIS. FOUND CROSSOVER DUCT ORIFICE 50 PERCENT BLOCKED WITH DEBRIS - CLEANED. CHECKED VARIOUS ORIFICES ON BOTH SIDES AND CLEANED. RAN PACKS ONE AT A TIME WITH MAX AC DUCT TEMP AND NO SMOKE OR ODOR.