What was found
CAPT SHOULDER HEATER INOP IN 'LOW'&'HI'. NO AIRFLOW AT ALL FROM GRILLES UNDER WINDOWS 2L & 3L. NO AIRFLOW NO HEAT. HEATER PCN 563-0014. CHECKED FOR AIRFLOW. NO DIFFERENT THAN FIRST OFFICERS SIDE. REPLACED CAPTAIN'S SHOULDER HEATER PER MM. OPS CHECK IN AIR MODE NO HEAT. HEATER OPS OK, NO AIRFLOW. MM 21-45-02-401 (SHOULDER HEAT) & MM 21-22-02-401 (FLOW ORIFICE) FOR DUCT LAYOUT. LOW FLOW COULD BE DUCT WORK ISSUE OR CLOGGED ORIFICE. CLN:CLEANED DUCT, OPS NORMAL.