As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOTS REPORTED THAT THE RT PACK PRODUCED SMOKE AND A BURNED ODOR ONLY WHILE ON THE GROUND. IN THE AIR IT WAS NORMAL. MAINTENANCE FOUND THAT THE GROUND COOLING FAN WOULD WORK FOR A MINUTE AND THEN QUIT. ORIGINALLY PLACED ON MEL AND THEN MAINTENANCE REMOVED AND REPLACED THE RECIRCULATING FAN PN AE1711AA0 SN ON 224 SN OFF 711. IAW MM 21-25-02. THE OPERATIONAL CHECK WAS GOOD.