As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INLET ON DUCT DEFORMED DUE TO HEAT RESTRICTING AIR FLOW. (COPILOT DEFROST.) SUBMITTER FABRICATED NEW DUCT OUT OF FIBERGLASS USING OLD DUCT AS PATTERN. DAMAGE DIFFICULT TO DETECT. SUBMITTER SUGGESTS REMOVING HOSE, CABIN FIREWALL, TO INSPECT.