As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAKEOFF THE CONTROL CABIN TEMP BECAME UNCONTROLLABLE, WENT TO 82 AND STAYED THERE EVEN WHEN OFF SELECTED. ACFT GROUNDED. REPLACED CABIN TRIM AIR VALVE IAW AMM 21-61-21. RAN BITE TEST FOR TEMP CONTROLLERS IAW AMM 21-61-00. ALL TESTS PASSED.