As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FWD CABIN TEMP CONTROL FAILED TO CONTROL DESIRED TEMP. BUSINESS CLASS CONTINUED TOO COLD. SHOWS 75 DEGREES. TEMP SELECTOR POSITION MUCH HIGHER THAN OTHERS. REPLACED AUX MID TRIM VALVE (NO HELP). PULLED AND COLLARD BREAKER H3 & H6 ON P11 PANEL. VALVE INDICATES CLOSED. SUSPECT ROTARY RHEOSTAT ITEM R571 FOR MID TRIM TEMP ON PACK PANEL.