What was found
WITH APU RUNNING WE RECEIVED AN AIR DUCT O'HEAT CAB CAUTION. CABIN TEMP WAS EXCESSIVE AND THE CABIN STARTED TO FILL WITH AN UNKNOWN SMOKE/ODOR THAT WAS EASILY VISIBLE. UNABLE TO CONTROL THE CABIN TEMP IN BOTH AUTO & MANUAL MODES. REMOVED CABIN TEMP CONTROL VALVE PIN 27241287-14 SIN 4BF2F BECAUSE OFNO CONTROL AND CODES ES AND E6. INSTALLED AN INSPECTED CABIN TEMP CONTROL VALVE PIN 27241287-14 SIN 9BW162F COMPLIED WITH SATISFACTORY OPS AND LEAK CHECKS. ABLE TO CONTROL THE CABIN TEMP IN AUTO & MANUAL MODES. OWERED UP AIRCRAFT & VERIFIED THERE ARE NO FAULT CODES ON THE TEMP CONTROLLER. COMPLIED WITH ANOTHER APU RUN & OPS & LEAK CHECKED WATERSOCK ASSY. CLOSED UP BAGGAGE FLOOR. TEMP CONTROL OPS CHECKED GOOD, NO SMELL IN THE CABIN. REF AMM21-51-00 AND 21-61-00