As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLIGHT 2801 - THE CREW REPORTED THAT DURING THE AIRBORNE PORTION OF "B" ICE TEST THE CREW RECEIVED AN EXTREME BURNING ODOR IN THE CABIN AND COCKPIT THAT LASTED ABOUT 30-40 SECONDS AFTER COMPLETION OF THE TEST. THE AIRCRAFT LANDED AT IAH WITHOUT INCIDENT WHERE MAINTENANCE INSPECTED THE AIRCRAFT AND PERFORMED THE ICE TEST "B" WITH NO DEFECTS NOTED. THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.