As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SMOKE/SMELL, ENROUTE, PILOTS REPORTED THAT SMOKE FILLED THE COCKPIT AND CABIN OUT OF THE HEATER VENTS. MX RE-INSTALLED A HOSE THAT WAS ASSOCIATED WITH THE LT PACK. CHECKS ON GROUND WERE GOOD. SUBSEQUENT OPERATIONAL CHECK FLIGHT WAS UNSATISFACTORY. MAINTENANCE REMOVED AND REPLACED THE LT HEAT EXCHANGER IAW MM 21-50. OPERATIONAL CHECKS WERE OK.