As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RETURNED TO SLC BECAUSE WITH ONLY THE LEFT PACK ON FLOW LIGHT ILLUMINATED. WITH CLIMB POWER AT 7000'. FLOW LEVEL AT 10000 TO RETURN FOR LANDING, CABIN CLIMBED TO 7000'. VERY HOT IN CABIN. FOUND LT FLOW CONTROL VALVE STICKING INTERMITTENTLY. REPLACED LEFT FLOW CNTL VALVE PER M/M. LT PACK FLOWS NORMALLY AND SUPPLIES 40 DEGREE AIR.