As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CONTROL CABIN TEMP SPIKES FROM COLD AIR TO FULL HOT WHEN CONTROLLER KNOB MOVED FROM POINTING TO THE B IN CABINE TO THE WHITE DOT JUST A SLIGHT BIT TO THE RIGHT. STAYS UNCOMFORTABLY COLD. ACFT GROUNDED. REBOOTED ACFT POWER. PERFORMED IAW AMM TASK 21-61-00-700-807-002. CHECKED GOOD. NO HISTORY IN 30 DAYS. OPS NORMAL.