What was found
UNABLE TO INCREASE FLIGHT DECK TEMPERATURE, CONTROL CABIN SELECTOR HAS NO EFFECT. WITH SELECTOR SET TO MAX, WARM, CONTROL CABIN TEMP HOLDS AT 28 DEGREES C, FLIGHT DECK VERY COLD. ACFT GROUNDED. ACCOMPLISHED FIM TASK 21-61, TASK 861 K.2. EXAMINED AREA AROUND TRIM AIR PRSOV & FOUND SENSE LINE BEHIND VALVE DISCONNECTED. RECONNECTED SENSE LINE. PERFORMED TEST OF THE TRIM AIR PRSOV IAW TASK 21-61, TASK 861, K3. AIR OPS CHECK NORMAL.