PERFORM 13 POINT TUNE-UP FOR 9YR HEATING SYSTEM. CHECK ALL ELECTRICAL CONNECTIONS. CHECK MANIFOLD GAS PRESSURE AND FOR PROPER VENTING. CHECK BURNERS AND BURNER OPERATION. LUBRICATE ALL NECESSARY MOVING PARTS, ADJUST BLOWER COMPONENTS. CHECK THERMOSTAT, AIR FILTER, AIRFLOW, ENERGY CONSUMPTION, FAN CONTROL, AND CHECK HUMIDIFIER. FOUND RUSTY COIL, NO LKS.