As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BURNING SMELL & SMOKING HAZE SEEN COMING FROM GASPER WITH HEAT IN MANUAL AT FULL HOT. STOPPED WHEN HEAT WAS TURNED OFF. R & R ACM DUE TO LEAKING OIL INTERNALLY. OPERATIONS CHECKED CABIN HEAT SYS IAW MM 21-60-01. CHECKS GOOD, OK FOR SERVICE.