As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, AIRFLOW THROUGH GASPER VENTS IN COCKPIT DIMINISHED TO ZERO WITH NORMAL DUCT PRESSURE INDICATING ON GAUGE, WITHIN MINUTES AIRFLOW RESUMED AT A VERY COLD TEMP AND BITS OF ICE WERE OBSERVED COMING OUT OF VENTS. ACFT GROUNDED. PERFORMED PACK/ZONE TEMP CONTROLLER BITE TEST IAW AMM 21-61-00-700-806-002, NO FAULTS NOTED. GREEN GO LIGHT ILLUMINATED. RAN LT PACK, OPENED LT ACCESS DOOR, FOUND TCV VERY HOT TO THE TOUCH. REPLACED TCV AMM 21-51-10-400-801.