7YR HEATING UNIT SCHEDULE FOR CLEAN & CHECK-UP. CLEAN AND CHECK BURNERS AND BURNER OPERATION. CHECK HUMIDIFIER, THERMOSTAT, AIR FILTER, AIRFLOW, HEAT EXCHANGER, HIGH LIMIT CONTROL, ENERGY CONSUMPTION, FAN CONTROL, AND ALL ELECTRICAL CONNECTIONS. ADJUST BLOWER, AND LUBRICATE ALL NECESSARY MOVING PARTS.