What was found
(CAN) CREW REPORTED REDUCED AIRFLOW THROUGH CABIN VENTS. MAINTENANCE DISCOVERED FORWARD HEATER NOT WORKING. BLOWER ASSY REMOVED (P/N EM630-2/114-380028-5) AND UPON INSPECTION, FOUND TO BE VERY STIFF TO ROTATE. RESISTOR COVER REMOVED AND IT WAS DISCOVERED THE 2 RESISTORS HAD MOVED OUT FROM THEIR HEAT SINK (ONE BY 11.0 MM THE OTHER 5.4 MM). ONE RESISTOR SHOWED SIGNS OF HEAT DAMAGE AS WELL AS BEING CRACKED AROUND ITS CIRCUMFERENCE. FWD BLOWER REPLACED. SUBMITTER SUGGESTS SETTING AN OVERHAUL TIME LIMIT ON BLOWER.