What was found
COCKPIT TEMP SELECTOR (CONTROL CABIN) DIFFICULT TO CONTROL TEMP AT ALTITUDE, SEEMS TO PROVIDE COLDER TEMPS VS PROVIDING HEAT WHEN ADJUSTING TEMP. GROUNDED - YES. BITE PACK TEMPERATURE CONTROLLER AND NO FAULT FOUND. REF B737-800 FIM 21-62-00-810-801. REMOVED AND REPLACED CABIN TEMPERATURE SENSOR FILTERS REF B737-800 AMM 21-61-06-400-801. SUPPLY CONDITIONED AIR TO CONTROL CABIN WITH BOTH PACK AND CABIN TEMP IS COTROLLABLE REF FIM 21-62 TASK 905.