As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TROUBLESHOOTING OF HEATING DISCREPANCY THE COMBUSTION TUBE OF HEATER WAS FOUND SEVERELY COMPRESSED AROUND ITS UNSUPPORTED CIRCUMFERENCE. NO VISABLE CRACKS OR LEAKAGE WERE NOTED. SUSPECT WEAK WALLS FOR A PRESSURIZED INSTALLATION HEATER ASSEMBLY WAS REPLACED WITH FACTORY REBUILT ASSEMBLY.